By on February 3, 2010

Update: a portal to all of TTAC’s articles on the subject of Toyota gas pedals is here:

Toyota has sent instructions and the shims for the field fix of the recalled sticky CTS gas pedals to dealers as of today. We have obtained the instructions (pdf here) [Hat Tip: Roxer], shims, and carried out the fix on a new CTS pedal accordingly. Follow along as we carry out the fix, and how we arrived at our unhappy conclusion.

The CTS pedal has a friction arm that is designed to generate a certain degree of friction necessary for the proper functioning of the electronic gas pedal. In our earlier tear down and analysis, we pointed out that the CTS design is inferior to others, such as the Denso unit also used in Toyotas. The friction arm is subject to wear and contamination that increases friction to the point of creating a sticky gas pedal.

The friction arm is a pivoted fulcrum; the end with the “friction teeth” rides in two grooved channels in the pedal assembly. Both these parts are made from plastic. The other end of the friction arm is held in place by the return spring, which exerts the pressure necessary to generate the friction. As the friction teeth wear, the gap on the other end increases in relation to the housing. Toyota’s shim is inserted in this gap in order to reduce/limit the amount of friction, and to compensate for wear.

The gap is to be measured by a feeler gauge (photo above), which determines the thickness of shim that is then inserted in the gap. The shim then limits the travel of the fulctum on the spring end, thereby reducing the amount of friction on the teeth as they ride in the grooves.

The next step is to open the gap by inserting a narrow-shank screwdriver, so that the correctly-sized shim can be installed. The unit has been turned upside down to facilitate that.

The shim (gray steel)  is now slid in, and positioned behind a lip that serves to retain it. The shim is kept in place by the pressure of the return spring on the fulcrum, but we wonder whether a strong jolt might not be able to dislodge it. If it did become dislodged, it could potentially cause serious  problems. No one would ever design a unit like this with a loose metal shim that was held in place by spring pressure only.

The next picture shows the shim all the way in place behind the lip. It’s a good thing that lip exists, otherwise this fix would not be possible.

The photo above shows the inside of the unit, with the friction arm extending forward. The shim is clearly visible as the shiny gray rectangle. The pivot axles extending out on both sides of the fulcrum/friction arm are visible as two small white/gray pieces, just below and to both sides of the shim. The friction teeth are visible  towards the front of the unit, riding (now higher) in their grooves.

This photo above was taken previously of the same pedal. It’s difficult to tell exactly from the slightly different angles whether the teeth are riding higher with the shim, but it does appear so. And a subjective impression was that the pedal had somewhat less friction. So the fix may well reduce the friction below a dangerous level, but for how long?

The only way we interpret the necessity of measuring the friction arm gap and choosing an appropriately sized shim is that the older units with more wear will have a smaller gap than the new(er) ones. The shim will compensate for that wear, but in a static, not dynamic way. As soon as the continued wear on the friction arm changes its size or other friction characteristics, the pedal is potentially back to the same sticky situation as before.

The shim’s effect on reducing the amount of friction will presumably slow down the wear process, but intrinsically, this is not a permanent fix to a very critical part, from a safety point of view. This is why the CTS-type pedal design is flawed, because it is subject to changes in the amount of friction it generates due to wear and other factors.

The only other explanation for the varying gap size and different shims is that the manufacturing tolerances are so great, that this is necessary to compensate for them. That’s that hard to imagine, for such a critical part. But if so, it raises other serious questions about this unit. Either way, it reinforces our position that Toyota needs to replace all the CTS pedals with Denso pedals or another proven pedal design, as soon as they are available. The shim fix is a Band Aid, and does not inspire the confidence that Toyota urgently needs to instill in its customers and the market place at this critical time.

Update: Given that Toyota has acknowledged that these pedal assemblies cost them $15, it would obviously be cheaper (and more reliable) to swap out the CTS units with the Denso unit rather than this fussier and riskier fix. The problem is time; it could take many months if not a year or more to change tooling and produce 2.3 million units. Meanwhile, making these shims was obviously something that a stamping manufacturer could do in days.

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100 Comments on “TTAC Does The Toyota Pedal Shim Fix: Stop Gap Solution At Best...”


  • avatar
    twotone

    Nice of Toyota to stamp a “this end up” arrow on the shim.

    Twotone

  • avatar
    Roxer

    Very well done Paul.

    One things that strikes me as strange is that there is a tab that the shims essentially mold right into. The only function of this tab seems to be to fit the shim in place. Without a shim it doesn’t need to be there.

    This makes me think that other manufacturers likely use a shim which would be an interesting direction to go from here. Or just to see a couple of different manufacturers gas pedals to see what the differences might be. I’d imagine the fundamentals are the same.

  • avatar
    redmondjp

    Thank you and kudos for your excellent description and pictures of the fix, not to mention the breaking-news quickness of the post!

    Hopefully this will put to bed the inaccurate descriptions of what the shim does that I have seen in some of the MSM pieces (“increases spring tension to ensure that the pedal returns to idle” etc).

    In the “good ol’ days”, they would have incorporated a locking set-screw adjustment on this friction piece, such that a commonly-available piece of test equipment (such as a spring force indicator that is used to check the spring tension of starter brush springs during a rebuild) could be used at the dealership to set the hysteresis friction consistently between throttle assemblies. “Shims? We don’t need no stinkin’ shims!” Or had different-tension (and color-coded) spring sets (as were used in the mechanical valve bodies on automatic trannies) that could be selected to set the proper friction level.

    But nah, we don’t design things like that anymore, do we? Adjustable? Huh?

  • avatar
    Greg Locock

    Good article but “It’s a good thing that lip exists, otherwise this fix would not be possible. ” sticks in my craw.

    They have developed a fix that takes advantage of a pre-existing feature. That is sensible, not grounds for a sneer.

    • 0 avatar
      Roxer

      Looking at the pedals in-depth myself at work here I don’t really see why that lip should exist in the first place.

    • 0 avatar
      dalava

      LOL… I am sure it was designed in feature in the first place to be used later for situations exact like this.

    • 0 avatar
      Roxer

      Why do you think it is there? :)

    • 0 avatar
      rlumpy

      Looks to me like the lip is intended to limit the travel of the pressure foot rocker, thus limiting the foot pressure to a constant value at large pedal deflection. In other words, you would have a linearly varying pressure on the foot until you reach a certain max value. The shim effectively decreases that maximum pressure setting to a value that won’t seize up under all possible wear/temperature/humidity conditions. By doing the fix in this manner, they keep the same pedal friction (“hysteresis”) at normally used throttle openings but avoid increasing the friction to a dangerous value.

    • 0 avatar
      ekaftan

      The lip was there for the shim. Then a ‘cost reduction specialist’ said it was unnecesary and cut it out… :)

  • avatar
    John

    Great coverage on this issue Paul. No other site or news organization has broken this down and given in depth descriptions of how the pedal and its proposed fix works. You have gone beyond the press releases and “guest experts” and have done what others can’t or won’t do. Somehow I think this is what reporting and commentary should be. Anyone can pass on a press release. It takes a little more work to investigate and analyze as you have done. Keep up the good work!

    BTW. What did you do, find a friendly service manager or parts counter guy who would let you play with their parts?

  • avatar

    I want everyone to drive down the price of Toyota’s stock as much as possible so I can buy in at a low.

  • avatar
    ajla

    There’s only one way Toyota can truly fix this mess.

    That one thing is to import the Toyota Century to North America and sell it for $27K.

  • avatar
    Kyle Schellenberg

    The variation in the wear as determined by the feeler gauge creates one other potential issue – what if Toyota dealers run out of one size of shim? Will they be inclined to just throw whatever they have in there without worrying about the consequence? A too small shim on a worn assembly isn’t going to reduce the travel enough. I’m not sure if they could even fit the larger shim in a less run down assembly, but if they could what affect would that have? (likely just an unnatural feel with the pedal).

    • 0 avatar

      Read the PDF with Toyota’s official recall instructions… they estimate repair volume for each shim size. 1.4 and 1.6mm shims are “low estimated repair volume,” 1.8, 2.0 and 2.3mm shims are “high estimated repair volume,” while 2.6 and 2.9mm shims are “medium estimated repair volume.”

    • 0 avatar
      YotaCarFan

      Why does each box of shims contain 10 of each size, when Toyota knows that certain thicknesses will be needed in much greater quantities than others? Depending on the number of boxes received by each dealer, they may run out of the popular sizes and be tempted to put in the next closest size.

    • 0 avatar
      Roxer

      Depends on the dealer, Yota. My dealer is very good about doing what is right – our first priority is their safety. An injured customer has a tough time paying a bill.

  • avatar
    Bill Wade

    I thought the same thing watching the news this evening.

  • avatar
    YotaCarFan

    Toyota is really asking for trouble with this fix:

    1. It requires precise measurements (feeler gauge). If the gauge is not held perfectly parallel with the pedal housing, the measurement will be off. My experience with Toyota & Lexus dealer service workers: Consistent sloppiness and incompetence.

    2. While the 1 in 5 inspection sounds good, the inspection doesn’t cover critical things like wrong shim size selection, and it doesn’t verify that the shim is properly centered (per step 9). Furthermore, the inspection doesn’t (as written) require removal of the pedal. The only QC thing related to safety is checking torque of bolts holding the pedal assembly to the firewall. Other steps are geared to prevent customer annoyance (pedal not wired in so car won’t go, radio presets wrong).

    3. The shim is not glued or screwed in place. So there’s risk it’ll move about and cause problems or fall out completely.

    4. The pedals work when new; they fail over time due to something, presumably plastic creep or rubber wearing down. This process will continue after the shim is installed. Will the shim that’s carefully measured to fit today be the proper size in a few years after pedal parts wear down?

  • avatar
    lahru

    Rube Goldberg would be proud!

    • 0 avatar
      Paul Niedermeyer

      Roxer,
      It fit reasonably tight enough. But the only thing holding it into place is the pressure from the spring. The lip only positions it, but wouldn’t hold it into place. The two shims I had were of different lengths (in addition to different thickness); I’m not sure that was because of a lack of “precision cut”, or because the different thickness demands a different length as part of the compensating mechanism.

    • 0 avatar
      Roxer

      Were you only given 2 of the shims? There are quite a few to choose from. I’ll let you know if there are multiple lengths.

  • avatar
    CarPerson

    LICENSED TECHNICIAN???

    Ok, I’ll bite: Tell me how to verify the technician is “licensed” in the eyes of Toyota.

    • 0 avatar
      Roxer

      A technician who has gone through the journeyman international training. has his ‘ticket’ as it were

    • 0 avatar
      YotaCarFan

      “Licensed Technician” means “anybody working at the dealership who read the instruction sheet and watched the supplementary video”. Note that Toyota’s CEO said some dealers will be open 24×7 to do the repairs — surely they don’t have enough mechanics on staff to cover all the shifts.

    • 0 avatar
      Roxer

      The licensing of a technician is a level achieved based on schooling and experience. It is an internationally accredited program.

      Whether a dealer follows the rules or not depends on the company.

      The work involved to do it – won’t take a rocket scientist to stick a piece of metal in a place designed to fit into the pedal.

  • avatar
    joemoc1

    In speaking with one of my clients who is a Toyota Service department Director, I was informed that they had received 50 of these shims to use on the 7000 cars in the dealership’s database that qualified for the recall.
    He was not provided a date on when any more shims would be made available.
    could be a while……

    • 0 avatar
      Roxer

      That is true. We are receiving 70 package of shims at 10 shims per bag. All in the various sizes. Won’t last us all that long. A week at most depending which is the most common sizes

  • avatar
    srogers

    I applaud the demonstration of the fix and the subjective assessment of the difference in feel.

    However I cannot agree that this experiment endows the experimenter with the knowledge or authority to proclaim that “Toyota needs to replace all the CTS pedals with Denso pedals or another proven pedal design, as soon as they are available”.

    How do you know that this doesn’t work perfectly well and will continue to for decades to come? Unless you are an automotive engineer with test lab behind you, I feel that this goes beyond investigative journalism and into whoring for web hits.

    • 0 avatar
      Paul Niedermeyer

      Would you accept some reasonable middle ground between your two extremes? I wish I had a lab and some engineers, but I don’t. I came to my conclusions from spending several days with both units, as well as being familiar with the problematic history of the CTS unit going back to 2007.
      I’m making a logical conclusion based on common sense, a degree of technical insight, history, and the fact that this unit is being recalled because of its intrinsic shortcomings. In my first tear down, I actually expressed that I thought the CTS unit looked sturdier in certain ways.
      But that’s not the key quality in the case of its friction generating mechanism. I stand by my conclusions. And I predict the odds are very high that Toyota will eventually replace these units with another design. In any case, I would, if it was my car. It’s an easy switch that anyone could do with limited skills.

    • 0 avatar
      Quentin

      Paul – I was an automotive quality engineer for over 3 years, up until Jan 1, when I rotated to production support engineering. I’ve seen many engineering changes come across my desk that were oh-so-slight but they fixed the issue in the field. The warranty data backed it up as well. Engineering is a game of microns. Considering this is a several millimeter shim, I’d say that it is going to have a pretty big impact on the amount of drag in the friction mechanism. Based on what I’ve seen of the pedal, the little ledge was the datum that the retainer rests on. The field failures could have been this ledge having flattened out which would create more interference between the friction mechanism. This shim is a much larger area than the ledge so the pressure on the plastic is lower. The slightly higher spring load is offset by a far larger area to distribute the load.

    • 0 avatar
      Juniper

      Quentin, Thank you, that finally makes sense. That is the first description that adds up.

    • 0 avatar
      Paul Niedermeyer

      Quentin, Not so. That little ledge always hangs in the air; that’s why the gap between it and the base is measured first with the feeler gauge.
      If it was as you thought it was, then your comment would make sense.
      The gap varies depending on the amount of wear on the friction element, and that slowly increases the gap on the other end, where that lip is. By inserting the shim, it reduces the force of the friction element by some degree.
      It may be hard to fully comprehend how this unit works from my pictures; a video of the whole thing would have been better. It wasn’t possible.

    • 0 avatar
      Quentin

      Paul – the print that Toyota released shows that ledge as where the retainer rests against the pedal housing. Are you sure that the feeler gauge isn’t measuring the distance between the pivot and the housing? A video would be appreciated.

    • 0 avatar
      Paul Niedermeyer

      Quentin,  The Toyota drawing is misleading and wrong. It shows the pivot arm resting on that lip. In reality, it doesn’t, and I have the pictures to prove it. Go look at the third picture in this story:
      http://www.thetruthaboutcars.com/toyota-gas-pedal-fix-simulated-friction-reduced-but-by-too-much/
      the gap is there perfectly clear. I have other photos of the gap to prove it.
      The pivot is designed to be in a dynamic relationship, with the spring pushing one end, and the other engaging the friction teeth. It has to “swing” freely in order to do that as designed. Putting in the plate raises up the teeth, but takes away the dynamic quality of the whole assembly.
      I may do some drawings and another post to explain this further, because it’s the heart of the issue, and why I don’t like this fix. It’s very much a jury rig solution.

    • 0 avatar
      Juniper

      Paul
      Good Job. Now I think I understand. By putting in the spacer they are essentially eliminating or drastically reducing the the load on the friction device. By doing so they are also eliminating the chance of jamming. I wonder how different the pedal feel will be. I am just going to assume you already have an owner out there that is going to report on the whole experience.

  • avatar
    CarPerson

    Ask that a copy of the “Licensed Technician’s” license be stapled to the repair order along with a signed and Notarized statement that it was he or she that actually did the work???

    Without these two documents, when the fix fails, Toyota will blame the customer.

    • 0 avatar
      Philip Riegert

      Gotta love the distrust of the dealership. If only you could all work at a dealer for a month you would understand. Sure some dealers out there are crooked – same as any industry. But the majority are in the business to fix cars.

      Will an apprentice do the work instead of a licensed technician? I’m sure it will happen. Looking at the amount of work required – even I could do it. Doing it correctly won’t see to be a matter of having someone who has worked on cars for 20+ years.

    • 0 avatar
      CarPerson

      It is TOYOTA that demands the work be done only by a “Licensed Technician”. So far, people are only guessing what license Toyota has in mind.

      I am aware of ASE Certification, but if that is what Toyota wanted, they would have said so.

      By not clearly stating what “licensed technician” they are referring to, you have no way of complying, which is exactly what their lawyers want. These people are far from stupid.

  • avatar
    Strippo

    I can open the throttle on my car by depressing the gas pedal even with the battery disconnected. There’s your fix.

  • avatar
    Aqua225

    A shim? They’ve gone for broke on DBW anyway, why not have the accelerator return done by a servo motor? Then they could adjust the return pressure based on software. Just have a pedal with a servo motor that is always trying to obtain “no throttle”. Then you lift, it goes back. Change the software to control the amount of torque the return servo applies to the pedal ;)

  • avatar
    fgbrault

    Good article. I hope you sent copies of it to NHTSA and Toyota!

  • avatar
    shooty

    Nice explanation of repair procedure, I did my first one today, as far is my dealer is concerned, they will not stay open later. our manager says he,s not gonna pay overtime to are techs,but are manager is a complete moron

  • avatar
    Bill Wade

    <A shim? They’ve gone for broke on DBW anyway, why not have the accelerator return done by a servo motor? Then they could adjust the return pressure based on software. Just have a pedal with a servo motor that is always trying to obtain “no throttle”. Then you lift, it goes back. Change the software to control the amount of torque the return servo applies to the pedal ;).>

    That's the WORST thing you could do. This may be somewhat OK in a "money no object" application such as fly by wire systems in military and commercial aircraft with multiple redundant systems but not in mass produced inexpensive systems where it's a critical safety item.

    I have some personal experience with servo motors and their failure when I lost both the primary and secondary synchro servo steering systems on a guided missile frigate. High dollar equipment that was tested daily and they failed during a refueling operation causing ship damage and personnel injuries. I was responsible for said units and took pride in my work. I was cleared in a board if inquiry but the fact remains, additional complexity causes additional failures.

    I remember an old saying we used to have, "The Fail-Safe Theorem: When a Fail-Safe system fails, it fails by failing to fail safe."

    Many times the simplest solution is in fact the best. I'll give Toyota the benefit of the doubt here. If their (and CTS's engineers) actually think this won't work then they wouldn't be doing it. If this fix fails and more people are killed or injured, both companies will face dire consequences.

    • 0 avatar
      Quentin

      I was hoping someone would pipe up with the reliability of a servo. I don’t have much experience in them, but it seems like you’d have to have one hell of an overbuilt servo to handle the life of a car.

    • 0 avatar
      rlumpy

      Actually the throttle plate in a drive-by-wire throttle is controlled by some kind of a servo motor. It usually lasts the life of the car.

    • 0 avatar
      Aqua225

      I was mostly saying this as tongue in cheek, hence my winking smiley at the end…

      But I also think the shim is a bad idea. These things aren’t really made to be serviceable parts. Toyota is pretty confident the fix is not going to compromise the structure, at least one hopes :)

  • avatar
    JOSHUAD

    I am a Toyota Tech. I’ve read some post on here. There is no such thing as a “licensed tech”. Unless you are talking about his/her driver’s license. I did 3 of these today. Very easy. The shim will not come out of place. Even if it came loose gravity will keep it in there. Maybe its not the best fix, but its a start. Plus we as I know it have had only 12 complaints of the stick gas pedal happening out of millions. 12 which were not duplicated. In the history of vehicles. No manufacturer, not Ford, not GM, Not Chrysler, not anyone has ever stopped selling cars for a campaign/recall. The fact is they all would rather pay the fines and save money. Don’t forget Chevy and Ford have both sold cars that caught on FIRE!. Never stopped selling em. Go ahead attack.

    • 0 avatar
      Catherine

      In the history of vehicles?? Wow.

    • 0 avatar
      JohnAZ

      Joshuad,
      I believe you that sticky pedals is not a real safety problem. I haven’t heard of any deaths attributed to a sticky pedal that was slow to return. The other problem(s) of mats/pedal interferance, electronics, or missing brake override seem to be what caused ‘unintended acceleration’ which led to deaths. They are the real problems.

      In my view, this whole CTS sticky pedal fiasco was spun out of control by Toyota, NHTSA, and the press. It is a red herring and has nothing to do with the real safety incidents.

    • 0 avatar
      AccAzda

      JEEZ,
      That’s really helpful.

      Remember, this ALL stems from the fact that the NHTSA’s Lahood (leader) decides that all of these accidents have to lead to something, and apparently Toyota didnt want to own up to it. Then there are stories that Toyota wanted to keep selling the cars before the fix was in.. saying how it was a wear related part (as if the whole car isnt) and to bring it back then. — Thats how they got involved with the govt to be investigated (Ford Exploder / Firestone scale). SO the recall.. isn’t just the usual Toyota being safe.. its the GOVT / NHTSA saying.. you NEED to do this.

      How many companies had issues like this.. and continued to sell cars?
      How many companies were FORCED by the NHTSA to STOP selling the cars.. because the GOVT had to go to JAPAN to speak with TOYOTA to make them stop selling the cars.. and or receive the largest fine in recorded auto history.

      Point is.
      TOYOTA didn’t STOP producing or selling the cars out of the GOODNESS of their own hearts.

  • avatar
    Tweak

    A very strange way to induce hysteris in the foot pedal. The pedal could of been designed as the ones using a cable used to be. A bit of firmware could simulate the friction bit to the throttle and take out the jitter.

    As mentioned by just about every body except the press how come there is no fail safe tied to the brake?

    We own a Highlander,special order made in Japan, and a Lexus 460. No fail safe in either one. Duh. The Lexus has the pedal hinged on the floor just like my Studebaker used to.

    • 0 avatar
      YotaCarFan

      I’m not sure why some say a pedal hinged from above is more prone to getting jammed by floormats than one hinged from below. If the pedal is hinged at the floor, wouldn’t a floormat that creeps forward end up on top of the pedal and weigh it down?

  • avatar
    zduffey

    heelo first exelent artical Iam a yota tech.THe whole thing Idont understand about this whole thing is the cts pedals are just getting the shims now and densos are getting cut and ecm reflash.the high end of the stick says that lator on in acouple months we are going to cut sand the cts pedals and reflash why not do it now when they are in for the shims?When people come back for the reflash and shave they are going to think we didnt do it right the first time but in fact just a first stage.I was half temted today to try the calibration on the cts cars.I am shure it would work they have the same ecms just different pedals.The other thing Ijust love lol first toyota said just yesterday no lexas models will be included no today say es and is models

    • 0 avatar
      AccAzda

      SERIOUSLY,

      They make 6-7 vehicles out of the Kentucky plant all based on the Camry frame, Camry / Avalon / Highlander / Sienna / Venza / RX / ES and the SCION xB or xD.

      Ya CANT tell me the parts are different for the pedals…
      Ya don’t have to be a rocket scientist to figure that one out..

  • avatar
    tuckerdawg

    will a shim pedal be installed in a toyota to see what the real world impact on performance is?

  • avatar
    Detroit Todd

    So, can we say they lied now?

    It wasn’t driver error. It wasn’t about the floormats. It’s not about the pedal, or the shim.

    At long last, does Toyota have no decency, sir?

    • 0 avatar
      psarhjinian

      Except that most SUA instances are driver error, at least one well-publicizes SUA case was the floor mats and I’m pretty sure Toyota wouldn’t stop production and eat crow if the shim was a stop-gap.

      But let’s not miss a chance to be dramatic.

    • 0 avatar
      JOSHUAD

      I think we will see a lot of people take advantage of Toyota. Saying there pedal got stuck, but knowing they themselves caused the accident. Who is lying?

    • 0 avatar
      Catherine

      DT, I’m inclined at this point to agree with you. I’ve found multiple postings all over the Internet of people who described SUA events with Toyotas that clearly were not sticky pedals or driver error, and these posts date back a few years, long before any recalls or any significant media coverage. And I’m still not convinced the “well-publicized case” was floor mats. Even if the car had the wrong mats, double-thickness, in the wrong place, it isn’t a slam-dunk that the mats caused the acceleration. Before that car ever got onto the freeway it had to have stopped a few times. Why did the mat problem not kick in until the freeway? And since an obstruction under the pedal, even a mat, is usually obvious to the driver, why not just pull it out? I’ve done it a few times in my driving lifetime. Maybe the driver couldn’t figure it out, or they were permanently stuck. But if most of these other cases are driver error, why are they predominantly occurring with Toyotas? If driver error is the primary cause, the numbers should be pretty consistent across all makes and models, and from what I’ve heard, they are not. Toyota has had more cases than several other makers combined, including Ford and GM.

      Whatever. My mother just traded her Toyota for a Nissan, and we’re both relieved. For the time being. Speaking of drama, Toyota just has too much of that going on right now.

    • 0 avatar
      JOSHUAD

      Watch out Catherine. I believe CTS makes pedals for some Nissans

    • 0 avatar

      I’m pretty sure Toyota wouldn’t stop production and eat crow if the shim was a stop-gap.

      Actually, the shim is precisely a stop-gap. It’s a spacer that fills the gap between two parts.

  • avatar
    Detroit Todd

    Really, Psar? Really?

    Are you prepared to ignore the previous investigations into this very issue? (And just because NHTSA couldn’t make a case, doesn’t mean there wasn’t an issue.)

    Really? When Toyota’s entire existence has been fixed to their “quality”?

    If this were a Chevy or Buick recall — hell, even a VW recall — you’d be singing a much different tune.

    In closing, I can’t think of a better situation in which to be dramatic as when people are dying and killing others because of their choice of car, particularly when said car was supposed to be “bulletproof”.

    I don’t think I’m being dramatic at all. Rather, I believe you to be unduly stoic.

    • 0 avatar
      psarhjinian

      If this were a Chevy or Buick recall — hell, even a VW recall — you’d be singing a much different tune.

      No, I wouldn’t. Because I’ve gone on many times before about recalls not being a direct measure of quality (depending on how you define “quality”). Recalls are rarely, if ever issued for non-safety related quality problems, and safety recalls (outside of food and drug) are rarely injurious to more than a handful of people.

      I’ll say this again: Toyota did not issue a recall for the sludge issue. GM has never issued a recall for it’s plastic intake manifolds. Honda has never issued a recall for the V6/5AT issues. Chrysler and Ford have never recalled their automatics. Each of those is a bona-fide quality problem, and each affected thousands of people.

      Recall magnitude certainly isn’t a measure of quality: if Ferrari had a recall for 100% of the cars it made in the last ten years, you’d be talking barely a few thousand cars. If Toyota, VW or GM recalls so much as a light bulb, it’s going to hit hundreds of thousands. So what’s worse, the company that can’t get any of it’s bespoke cars right, or the one who has to recall one percent of it’s million-unit-sales model?

      In closing, I can’t think of a better situation in which to be dramatic as when people are dying and killing others because of their choice of car, particularly when said car was supposed to be “bulletproof”.

      How many incidents have people supposedly died from. Come on, let’s see actual, proven numbers, not conjecture. Because in terms of “defects that kill people” this is actually pretty low, percentage-wise. Ford/Firestone saw more carnage. What’s happening, as per Mr. Karesh’s article and subsequent comments, is that no single defect scares people more than a car that accelerates out of control. Not steering lockup (which has the potential to be very deadly), not wheel separation, even though the solution to SUA is really very simple (neutral).

      So far, we have one dramatic case where the incorrect floor mats were installed incorrectly and a driver panicked. We also have another where a carload of passengers did die, but no one’s been able to prove the pedal stuck, only that the floor mats were in the trunk.

      What we also have is a manufacturer recalling five, possibly six million cars for an exhibited defect rate of less than one tenth of one percent. And we have people who are trading in their cars as a result, a media circus that completely misses the point and a congressional committee on the matter?

      I don’t think we had congressional committees when the Chinese were shipping melanmine-laced foodstuffs.

      Of course I’m stoic. I’m being realistic. I have a much better (worse?) chance of having a heart attack, slipping in the shower or, choking on my own vomit, burning to death in a house fire, or being killed riding a bicycle than being killed by an velocity-inflicted Toyota in my possession.

      What burns me the most is the rampant opportunism. From the lower-class media trying desperately to work this story to polticians trying to “do sumfin” to competitors using people’s fear for crass commercialism to brand-fanatics feeling their oats, I’m more than a little annoyed.

    • 0 avatar
      shaker

      Would it be fair to say that Toyota has become the “Tiger Woods” of the auto industry?

    • 0 avatar
      John Horner

      “I don’t think we had congressional committees when the Chinese were shipping melanmine-laced foodstuffs.”

      You might not think so, but we did. How quickly people forget. There was also new legislation and more money for the FDA.

      Toy safety (lead paint, etc) was very much in the news in 2008 as well, and that led to a new set of laws holding importers and retailers accountable for the safety of the products they sold. Previously, it was generally only the manufacturers who were accountable.

    • 0 avatar
      FromBrazil

      Wow, all the Ferraris ever made being recalled as not one of them ever works, ever. Now that’s dramatic. And brand fanatics feeling their oats or something (what does that mean…sorry my English is failing me again) whatever that means sounds dramatic, too.

    • 0 avatar
      YotaCarFan

      For the heck of it, I googled “unintended acceleration Chevrolet”. In addition to the usual assortment of people filing complaints on NHTSA.GOV for their Lumina, Malibu, Cobalt, and other models of Chevrolet allegedly accelerating by themselves, I found a Jan 2008 consumer reports article about 36,000 Chevy Aveo and Pontiac Wave cars being recalled b/c their throttles have a habit of icing over and sticking open, even after two previous service campaigns had been performed. Somehow I don’t recall seeing non-stop media coverage of that. So, I have to agree that the media’s response to the Toyota pedal problem is hyped for some reason other than it being a safety issue.

  • avatar
    zman

    I used to own a 2004 Chevy Aveo, which I traded in last year for a 2009 Toyota Corolla because of all the problems I experienced with it. The engine died just after 56,000 plus miles and they installed a rebuilt engine into it to get me on the road. Thank the Lord that I had enough common sense to buy an extended warranty with zero deductible from the dealer or else I would have faced enormous amount of out of pocket expenses.
    I had a problem with this vehicle at one time and it was that the engine over revved in idle, which would seem similar to a sticky accelerator problem. I am wondering if there are other companies besides Toyota that have the problem Toyota now has, but no one has said much about this? I read an article that CTS makes parts for other companies like Ford, GM and Honda..
    I never did take the car to the dealer to have it fixed but did pray for the problem to stop and it did and things became normal again. The Chevy Aveo had a Korean engine in it, a Daewoo one.
    I always treated that car right by getting the required service done on time, but it came with a lot of problems. The Chevy dealer’s service department knew me by first name and I got to befriend the Service Manager as well. My service writer eventually called my car the green monster. I thought going back to a Toyota vehicle would be better in the long run, I had great experiences and long driver miles on the 1984 and 1989 Toyota Camrys that I owned in the past. Was I wrong in doing so? Toyotas were highly rated by an Independent Consumer magazine that we all rely on for it’s opinion.
    My feeling about the accelerator problem in Toyota could also be linked to all the models that have cruise control. With Cruise control you can go faster or slower or keep the car at a certain speed. I believe this is linked to the inboard computer in the car that in some models may be flawed, as in the case of the Lexus and Camry accidents that happened last year. Maybe both vehicles were driven on the highway in cruise control mode and the problem developed and the engine did not disengage from the cruise control when the drivers attempted to do so. It went into acceleration mode. I remember seeing an article by someone else that mentioned this. Could this be a possibility? If so, all Toyota owners should refrain from using the car in cruise control until further investigation is done into this.
    I have also seen in pictures and looking at my gas pedal where the pedal is hooked up electronically, could this be more harmful than helpful? I understand this is to provide the car with extra gas mileage. I would rather pay an extra few cents at the gas pump than trust a computer in a car with my life. What do you think?

    • 0 avatar
      Britlass

      Zman – planes are flown by computers – they can take off, fly and land all by computers and often do. Computerization of our machines is inevitable I am afraid. Statistically it is likely that human error is more common than computer error. A lot of plane crashes are human error. Still, I agree that giving up that control is a scary concept.

  • avatar
    JohnAZ

    Paul,
    Once the shim (“precision cut steel bar”) is inserted and the pedal assembly reinstalled, what is the shim’s relative position to the floor? Is it horizontal? vertical? resting against the lip?

  • avatar
    JohnAZ

    If the ‘sticky pedal’ problem is a result of wear or contamination, it would seem that it would come on slowly over time. ie. People would start to have occasions in which they might notice the pedal returned a bit slower than normal. They would experience this as the car not slowing down as quickly when they let off the gas. They might even get used to it. At some point they would start to have occasions when the car momentarily doesn’t slow down at all. That would be very noticeable and would likely prompt a visit to their dealer.

    I can’t imagine that their first experience (unless they are in a rental) would be a lengthy failure to slow down after they lift their foot. It doesn’t make any sense that there would be numerous people reporting ‘unintended acceleration’ because of this ‘sticky pedal’.

  • avatar

    Paul, thanks for this great report. Could you take apart gas pedals of some older (“dead-reliable”) Toyota and also other modern cars to see how they design their reliable gas pedals, and post their photos?
    It would be very interesting to see the differences.

  • avatar
    Bruce from DC

    I find all of this very interesting. As a non-engineer, I’m wondering why the Denso solution of using friction of the spring against the two sides of the housing is inherently better than the teeth-and-groove method of the CTS product. It seems like that would be prone to environmental effects, dirt and wear, too.

    But what really astounds me in this value-engineering driven world is why Toyota didn’t just use a piston and cylinder with viscous fluid throttle damper (i.e. a “shock absorber”) to accomplish the goal of damping pedal motion. Being a closed system, it would be unaffected by changes in the external environment and any change in performance as a result of wear would be benign (less damping rather than more).

    Obviously, a cost issue.

    What’s interesting is that, in the early days of non-electronic efforts to control emission, such a device was used to prevent abrupt closing of the throttle plate (which apparently caused a little burst of unburned fuel in the exhaust).

    So, it’s not like this hasn’t been done before.

    • 0 avatar
      Contrarian

      I believe that device was called a “dashpot”.

    • 0 avatar
      DaveDFW

      Dashpots on carburetors predate emissions concerns. They were there mainly to prevent an engine from dying from the throttle being closed too quickly.

    • 0 avatar
      Paul Niedermeyer

      I agree; and would have expected to see some type of more sophisticated sealed friction device in these, one that ideally could be adjusted to provide more or less friction as needed or desired. I’m surprised at how crude this device works, and that the problems have arisen as a result of it.

  • avatar
    LiarLoan

    As someone who has worked his entire life in the automotive business, from technician to zone manager, I have to say this situation is a nightmare scenario for a car company.

    Whether or not there is a real problem with these pedals, every time one of these vehicles is in an accident the pedals will get blamed, and Toyota is going to lose.

    As a technician, I wouldn’t want to perform the recall, because EVEN if it corrects the problem, if an affected vehicle is EVER involved in an injury accident, the tech (and the dealership) WILL be named as defendants in the inevitable lawsuit.

    I suspect this may be the biggest cause for litigation in automotive history, since, unlike the pinto gas tanks, or the explorer tires, ANY vehicle owner can claim “the pedal stuck” without ANY proof, and make Toyota the fall guy for causing an accident.

    Toyota should dig into their “deep pockets” and buy back every one of these cars as soon as possible.

    • 0 avatar
      JOSHUAD

      I Have to disagree with you Liarloan. I doubt a Tech would take any heat for doing his job. I will gladly to court to defend myself. I could see if a tech said he put in a shim and didn’t or maliciously did aomething to the pedal, but if it is found that the tech performed the install correctly, he/she would be fine.

  • avatar
    Facebook User

    Paul,
    when you had the friction arm disassembled, did you note any excessive wear at the pivot point? I’m having trouble seeing how wear at the pivot point could INCREASE the friction. Seems like if that lobe wore down, the friction teeth would engage a little less, not more. So that leaves dirt, or plastic shavings, or having worn thru the plastic “skin”, thus increasing friction as the likely culprits. Was there a lot of plastic “dust” in there? It also seems like (I could be wrong on this…) the harder or quicker you press the accelerator, the harder those teeth did into their grooves, thus partially defeating a sudden pressing of the pedal. Is this correct?
    Last, it seems like the shim might actually be designed to completely defeat the friction system. The real solution might be to just cut the friction arms off, but that type of garage logic doesn’t fit well into a corporate rework & recall campaign. With the shim, they can deactivate the friction arm without actually admitting they weren’t ever really needed. Your thoughts?

  • avatar
    Uncle Mellow

    Thank you for the clear description of how the pedal works and how the fix works. I think it will be fine from a safety point of view.The two different shim sizes are probably needed to allow for well-worn pedals and nearly-new pedals. The problem is that , with the shim in place , the pedal will no longer self-adjust for wear , and in time the car will become very unpleasant to drive as the friction dissappears completely.

    • 0 avatar
      Paul Niedermeyer

      Exactly my sentiments!

    • 0 avatar
      The7

      Do you think that it is less unpleasant to drive if there is no friction?
      In our olden day, we try to lubricate the cab cable to reduce the friction of the gas pedal. Don’t think that the friction shoe is really necessary for these drive-by-wire gas pedals.

    • 0 avatar
      windsurfertx

      To answer the question about being unpleasant to drive with no friction:
      Yes. it is unpleasant.
      I just had the shim put in today. I noticed immediately that there was no friction. None that I could detect. And I did not like it at all. It is like pushing on a spring, period. I’d like to take it back.
      Maybe I’ll get used to it.

  • avatar
    Bill Wade

    Whether or not there is a real problem with these pedals, every time one of these vehicles is in an accident the pedals will get blamed, and Toyota is going to lose.
    ________________________________________________________

    Sadly this is true and you can bet with the current political climate you’ll have the government helping to destroy Toyota. It is after all, a non UAW company and an enemy of the ruling party.

    ————————————————-
    Maybe the regime could give every Toyota owner a replacement GM.
    ————————————————-
    This scenario would destroy any car company in the world. Forced into a scenario like this I would just fold up US operations and pull out. Of course I would point out to all the dealers, employees and owners of my product to contact the PI lawyers for any issues. :)

  • avatar
    Ellen

    Yes, there have been Stop Sales before. I know for a fact that Ford put a Stop Sale on the Contour & Mystique models right after their introduction.

    The public is not aware of how many defects are caught at the factory and never make it to the dealer at all. Plus those that are caught at the suppliers.

    Thanks for this great series. Spent a lot of years on teams diagnosing, designing and implementing such fixes. This takes me back.

  • avatar
    tftftf

    We have a 2007 Camry XLE V6. It was one of the first ones delivered in San Antonio. I read that not all Camrys have the CTS pedal. If your VIN starts with 4T1 you must check to see. The accelerator will be labeled on the side. Luckily, ours has the Denso pedal so no further action is needed.

    I really liked this article. The author did a great job explaining the “fix”. After reading all of this, if our Camry would have had the CTS pedal, I would have paid to buy the Denso pedal for the Lexus ES 350 and installed it myself into our Camry.

    I’m a mechanical engineer and I’m not impressed. Why settle for this crumby fix from Toyota when people paid a lot of money for these cars? A Camry was about $2000 more than a similar Honda Accord, but no better of a car.

    I hate to say it, but my initial thought was that these problems were due to software glitches or computer malfunctions and not a switch. You have to remember that this is not a real “gas pedal” physically linked to the engine throttle. It’s more like playing a video game and providing input to the car’s computer (drive by wire). It’s up to the computer to obey (or not) the driver’s suggestion.

    • 0 avatar
      AccAzda

      I can almost answer your question.. and provide a few questions.

      1. I personally don’t “understand” how they could use a different supplier for the ES vs Avalon vs Camry and or vs Sienna / Venza / RX / Highlander and or the xB or xD. They are all on the same frame.. probably made in the same factory.. whats the difference in which vehicle gets which?

      2. I think but cant be 100% sure that the trim level of the Camry you purchased (XLE V6) top model, but probably under the Limited. In any case.. its a Avalon / ES under the badges. They are PROBABLY getting you to pay more because the car is at the level that the ES / Avalon are at, trim level wise, comparable to a EX-L V6 that Honda’s Accord is at and within $$ of the TSX / TL. Its a very minor money issue at that level in pricing.

      In lamens terms..
      The car you purchased is at the top of the Camry range = bottom of Avalon / ES range = Equal to Accord’s EX-L V6 = TL / TSX.

      I am a little teed off at how a shim… is going to fix said issues with a coupla million cars. (Im still poed that TOYOTA isnt recalling cars they should.. even though they are on the same line, doesn’t make sense.)

      As for why someone would think a Camry / Avalon / ES is a better car than the Accord..
      I could go into 2 dozen separate socio- economic issues involving the cars and sizes over the past 20yrs.. and those who bought BUICK.
      Then there are issues of who is drives the cars.. and the lack of skill in doing so.

  • avatar
    Pahaska

    There was a reported stuck pedal here in Austin this week that made the TV news. The guy made a hurried left turn at an intersection and the engine stayed at high power. He creamed a pole and ended up with a badly broken arm.

  • avatar
    A Shifty 1

    I’ll quickly throw my 2 cents in here, since I did a couple hours ago on the first post.

    1. In my opinion, The CTS pedal is not responsible for the sudden acceleration. The pedal might come of the floor slower, but it won’t get you from 20mph to 50mph in a few seconds without you stepping harder on the gas.
    2. I think, The CTS pedal might not spring up and decelerate as fast as it should.
    3. It is possible, The reason they use feeler gages to measure the gap is because… I read…that they switched from a Nylon 4-5 resin to a PPS resin….and they have different shrink rates… OR… it depends on the relative height of the two V – W friction pieces of plastic, how high the sit realative to each other. We are probalby talking about 0.50 mm [.020 inches] difference in measurement?
    4. I think the computer chips that run the pedal, that sense the input from the sensors, only need tiny little bits of electicty, kinda like static electricity amounts, to make the car take off, and accellerate. The CTS pedal fix is not an explanation of acceleration. The CTS fix is an explation for the root cause problem —> the engine does not de-trotlle, or slow down fast enough.

    I’ve got a question. Of the 60 cars that were “fixed” by toyota, which pedal were in the car. Which pedal did the cop have who got killed? What about the guy who is in jail in Minnesota. Where is the data, on which pedal is in which car that had sudden acceleration?

    Here is to safety..
    Thanks the Truth about cars,
    for letting usa ideas get out here.

    That’s it.
    Cheers,

  • avatar
    Britlass

    Just my observations….I bought a 2010 Rav4 right before all this blew up in the news, and here’s what I have noticed: Short little surges of power that occur occasionally such as the radio will go loud for a couple of seconds, and sometimes the car responds slightly too enthusiastically to the gas pedal, but does not continue to accelerate if I release the gas, although perhaps there is a split-second delay in response when I release the gas pedal. It is so subtle that I end up blaming it on myself by saying I must have pressed the gas harder than I thought, but I really do think there is a subtle intermittent electrical abnormality with these cars. It is not enough to make me want to take it in as I don’t think the problem is frequent or severe enough for them to find anything wrong; neither do I feel unsafe. But I will keep an eye on it. I have also noticed the little brief surges in engine power only occur at speeds between 20-35 mph.
    Question: the guy who had issues with the prius accelerating to over 90 mph recently: why on earth did he not shift to neutral??? I heard he slammed foot and hand brakes but why not neutral as well? Do folks just panic and forget? I have practised this maneuver a few times – it sounds awful but it works!
    Anyone else notice similar issues with their toyotas?

  • avatar
    John Horner

    I know this is an ancient thread, but I happened up a picture of a pedal sensor assembly for a modern Honda/Acura and was quite impressed by how much more substantial the design seems to be compared to either of Toyota’s designs. Have a look:

    http://info.rockauto.com/getimage/getimage.php?imagekey=1514402&imageurl=http%3A//info.rockauto.com/SMP/APS148_FULL.jpg


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