The Truth About Cars » cold weather The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. Sun, 27 Jul 2014 20:45:49 +0000 en-US hourly 1 The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars no The Truth About Cars (The Truth About Cars) 2006-2009 The Truth About Cars The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars » cold weather MEMOIRS OF AN INDEPENDENT REPAIR SHOP OWNER: Cold-Weather Cause-And-Effect (not “Tall Winter Tales”) — Part Two Sat, 23 Mar 2013 13:00:08 +0000

Well, it looks as though winter is about done—at least from my vantage point west of the Rockies; but I still have a few more “revelations” to relate on the subject. As I stated in my last entry, these experiences were all new to me, since I’d never lived where “true winter” driving conditions were a regular occurrence. So, without ado, and as “green” as spring vegetation, here are a few more of my cold-weather “discoveries”.

While I wasn’t unfamiliar with a parking brake (some call it an emergency brake—which may in itself be a subject for further discussion) stuck in the “applied” position, I soon found additional reasons for this to occur in true winter weather.

Typically, on the West Coast, I’d see parking brakes sticking mostly because the brake shoes (we’re talking about rear-drum systems here; as most vehicles in the U.S.—save for Corvettes and upmarket Eurocars—were so equipped at the time) were wet when the brake was applied, allowing the shoes to “bond” to the drums via the oxidation process. It seemed like the VW Buses of the day achieved the most notoriety for this phenomena—particularly unfortunate for the tech called upon to “unstick” them, if the “Plan B” drum removal process was necessary.

In true winter weather, besides the “wet shoe scenario”, there were other possibilities involving the actuating linkage under the vehicle.

The worst was—and still is—when moisture would get down in the actuating cable and freeze the cable within its housing. The remedy would first involve some form of in-field procedure to free the brake enough to get the vehicle to the shop—or at least allow it to be maneuvered for towing—where it could be thawed enough to effect further repairs. Those “in-field” procedures were an eye-opener for me, as I had precious little experience in dealing with the weather conditions associated with them! Of course, the solution centered on using the right “gear” to minimize the effect of the harsh environment—along with resetting the Attitude Control to the “Mind-Over-Matter” position. After going through all that, the customer would usually be happy enough just to have the brake actuation reset to “off”, and they would make a conscious effort not to use it during similar weather in the future.

Speaking of in-field procedures in harsh weather, I can still recall the pain in my fingers while trying to reset distributor contact points well enough to make the vehicle run well enough to get it to a warmer place in which to work on it. When the ambient temperature got down to anywhere near 10F, this operation—as technically simple as it was—could be a real challenge (and provided one more reason NOT to mourn the passing of ignition contact points, for sure)! This was true of any procedure attempted in such conditions where bare hands were necessary.

I also found that any of the vehicles fluid-carrying systems had to be completely free of moisture to operate properly in the cold. Typically, in my L. A. stomping grounds, a little emulsified moisture in the power steering system, braking system, or transmission wouldn’t make its presence known—in the form of erratic operation—during the winter.

During true winter, however it was a different story. I learned to make it a point to regularly change and otherwise properly maintain these fluids, so as to keep all traces of moisture out.

When it came to the PCV System, I’d never heard of the PCV Valve and its associated plumbing rendered inoperative due to the water vapor passing through actually freezing. I had wondered why vehicles produced for the true winter market I’d been working on had insulation over the PCV plumbing. I remember reading a Honda Service Bulletin involving the retrofitting of insulation around the PCV valve and some of its plumbing, for the purpose of—you guessed it—reducing the possibility of system icing, and consequential oil-leak issues due to the ensuing over-pressurizing of the crankcase! I can’t remember ever working on a vehicle actually experiencing a PCV icing problem, but it was all food for thought.

Another cold weather bogey I learned to deal with involved the vehicle starting system. Component condition and circuit voltage drop rose to an extremely critical level, in comparison to the level acceptable in the warmer climes of the Southwest. If the battery, starter, or associated relay(s) were marginal, you’d know it when the weather turned cold—even though those components seemed to work all right in warmer temperatures. All of the test procedures and standards I learned during my schooling took on a new relevance, now. If things were not up to those standards, it turned out they flat-out just didn’t work in the cold. I became a “believer” and learned the new level of “critical” necessary to keep my customers rolling without drama during the winter months.

Phil ran a successful independent repair shop on the West Coast for close to 20 years, working over a decade before that at both dealer and independent repair shops. He is presently semi-retired from the business of auto repair, but still keeps his hand in things as a consultant and in his personal garage


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MEMOIRS OF AN INDEPENDENT REPAIR SHOP OWNER: Cold-Weather Cause-And-Effect (not “Tall Winter Tales”) Sun, 03 Mar 2013 17:53:27 +0000

As long as it’s still the winter season in the Northern Hemisphere—more wintry for some than others, here in the U.S.—it seems appropriate to stay on that topic for a while longer, here on the “Memoirs” page.

Having spent much of my career as an auto tech and shop owner in the Southern California area, I really didn’t get much of an opportunity to solve cold-weather problems on customer vehicles—mainly because there just wasn’t (and still isn’t) much of that stuff going around, down there.

Moving to New York—and then Louisiana—in the ‘80’s quickly changed all of that.

Of course, most vehicles had carburetors back then; and compared to those equipped with fuel injection, they tended to be more susceptible to the cold—especially when accompanied by high-humidity conditions (of which there is no shortage in either locale).

This fact led to a number of personal cause-and-effect revelations, which, while unfamiliar to me, undoubtedly were familiar ones to the locals. They were interesting revelations, nonetheless; and I’m going to relate a couple of the highlights right now.

When it came to choke systems on most typical carburetors of the day, I found that choke setting was not terribly critical in SoCal, as long as the plate was fully open when the engine was warm. Yes, setting did become a bit more critical on “emissions” carburetors—and British vehicles always had to have a fully functional choke (technically referred to as “cold-start enrichment”), even on the typical Los Angeles “cold” start.

But drop the temperature down to anywhere at or below freezing, and any flaw—however subtle it may have been—made its presence known in no uncertain terms. Choke plate not closing enough? You might have to pump the living daylights out of the accelerator pedal just to get the engine fired and keep it running long enough to warm up, and run without stalling at idle. Choke vacuum break not operating (with a properly adjusted choke plate)? Sure, the engine would start right up, only to be shortly followed by pronounced “chugging” and massive amounts of black smoke out the tailpipe. On later “emissions” engines, the thermo-vacuum valves controlling this process would fail and cause the same sort of conditions. I personally owned a Honda Accord that experienced that problem. On GM cars of the day, even a “no-charge” alternator condition would cut power to the choke heater coil, and the choke would fail to open quickly and completely.

Unlike the “repair wiggle room” prevailing atmospheric conditions in the Southwest afforded, attempting some kind of witty bypass maneuver in true winter climes got you into more of a mess than biting the bullet and just making the O.E. system function by the book.

Another problem I ran across—especially during the winter in Louisiana—was a malfunctioning intake air control system wreaking havoc with vehicle driveability.

The customer would claim that they’d be motoring along without a problem—often at a steady state highway cruise—and the engine would lose power, and eventually sputter and shut off! If they’d let it sit for a few minutes, they could restart without problem, and resume cruise for about five to ten minutes before experiencing the power loss and stall all over again.

Now in Los Angeles, the only problem I had experienced with TAC (Thermostatic Air Control) on carbureted engines, was when the air door would stay closed off to cold air, and engine “ping” followed by “vaporlock” when returning to idle would ensue, due to excessive heat in the intake air. Yes, that problem would also occur—probably even more acutely—in the Deep South. Usually, the quick and temporary solution to that problem was to make sure that the air door stayed open to cold air only; without much concern for any consequence involving the need for hot air, at any point.

The strategy worked in the City of Lost Angels, but not in the State of LA. At least not for year-round vehicle use!

What would happen during the winter, if the TAC system was not providing enough heated air to the carb vis-à-vis the air filter housing, was the formation of ice around the throttle plate. If the ice buildup got heavy enough, it would literally shut off the engine! In the state of LA, it didn’t have to be really cold for this to happen, either. It could get so damp down there, ambient temperature only needed to drop to around 50F for that to happen!

The customer would always be surprised when they learned that this was the sole cause of the problem!

Stay tuned for more “revelations”, next week.

Phil ran a successful independent repair shop on the West Coast for close to 20 years, working over a decade before that at both dealer and independent repair shops. He is presently semi-retired from the business of auto repair, but still keeps his hand in things as a consultant and in his personal garage.

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Piston Slap: Shake, Shivers…so Roll! Wed, 11 Apr 2012 11:38:14 +0000


TTAC commentator Kitzler writes:

Hi Sajeev,

Quick question everybody ignores: I personally do not like racing a cold engine. My last two cars, a Dodge and a Lexus, both had automatic transmissions. When the engine was cold, Summer or Winter, worse in Winter, you had to rev the engine to 3000. before it would shift properly. Worse, the automatic would not shift into top gear until the engine was lukewarm, a couple of miles. Now here is the clincher, as the cars got older, the couple miles became three. What gives?

Appreciate an answer about racing a cold engine and why the damn automatic won’t shift properly, thanks.

Sajeev answers:

First off, this problem is multiplied when you are crazy enough to install a high-stall torque converter in your Lincoln Mark VIII. It’s bad enough with a stock stall speed unit, but add the looseness of a drag-racing worthy fanbox in your gearbox and you need even more throttle and more wait time before the car behaves normally. But you didn’t come here to read that, did ya?

This is normal for darn near any car with electronic fuel injection and an electronically controlled gearbox. Both are needed, as transmission behavior depends on the reading from the engine’s coolant temperature sensor. Yup, engine coolant is a fine bellwether to the future of your engine and transmission’s programming parameters. Let’s face it, a cold engine is not ideal for any driving condition. You want the motor to warm up ASAP.

Cold fluids are bad for performance, tailpipe emissions, and longevity of your car’s power train. A vehicle needs to be loaded up to get the fluids up to operating temperature ASAP, so the computer does just that. And once the coolant temperature looks peachy, the engine/transmission oil follows suit. Revving the engine to 3000rpm is a good idea, as opposed to stewing in “friction-filled” cold fluid at idle or trying to circulate this thick/cold stuff at 6000 rpm.

And here’s my point: you are NOT racing a cold engine from what you stated, you are doing exactly what is needed.

As to why this behavior is worse as cars age, well, that’s harder to say. Perhaps the coolant temperature sensor isn’t reading accurately: its internal resistance from cold to warm (to hot) is no longer linear. Perhaps old fluid has a viscosity problem that throws a monkey wrench into the system. Or perhaps it gets harder to overcome “the shivers” as we all get older. Which is why we all gotta roll the moment we wake up in the morning!

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry.

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