The Truth About Cars » thermostat http://www.thetruthaboutcars.com The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. Thu, 17 Jul 2014 20:36:40 +0000 en-US hourly 1 http://wordpress.org/?v=3.9.1 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 editors@ttac.com editors@ttac.com (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 » thermostat http://www.thetruthaboutcars.com/wp-content/themes/ttac-theme/images/logo.gif http://www.thetruthaboutcars.com Piston Slap: The Too Cool Miata? http://www.thetruthaboutcars.com/2013/11/piston-slap-the-too-cool-miata/ http://www.thetruthaboutcars.com/2013/11/piston-slap-the-too-cool-miata/#comments Tue, 19 Nov 2013 13:09:25 +0000 http://www.thetruthaboutcars.com/?p=653858 Capture

John writes:

Dear Sajeev,

Thank you for much good reading and practical knowledge for a very amateur do-it-yourselfer. My auto repair and maintenance skills are very limited, but I enjoy doing what I can myself. Even just the oil changes and having control of the materials used to perform it.

So you are looking for subjects, and here goes-this may resonate with any number of Miata owners. For about a year the CEL has been popping up a code (0126) that I read with a simple device purchased online that evidently means the engine is running too cold, which I have never even heard of, but why not? Insufficient combustion temp?

Anyway, I see that it must be the thermostat which is seriously buried in this car and beyond my meager skills to get to, much less reassemble.

Do you think there is any urgency to getting this repaired? Car runs just fine.

Thanks!

Sajeev answers:

P0126 always takes me back to my time as a wannabe car designer at CCS in Detroit: if I wasn’t spilling venom on the vellum I’d dabble in auto repair consultation. To wit, a good friend spoke of his Merkur XR4Ti that he left in Florida, missing it but hating how it always ate “engine sensors”. Now, as a self-proclaimed expert on all things powered by Ford’s EEC-IV fuel injection system, I found that rather odd. Further questioning lead to this comment: “Oh, I never drove it with a thermostat. It’s Florida, you don’t need a thermostat!”

***headdesk***

If only I knew better back then, I coulda put him in check: EFI systems run at a certain minimum temperature to ensure the motor’s ideal health and efficiency. If not, you run the system in open loop, instead of listening to inputs like the Oxygen Sensors, MAF meter, etc to keep emissions down, power up, liquid smooth idle, etc. Take the thermostat out of the system and the sensors are never consulted.

Is that happening in your Miata? It could be running in open loop. Or not: modern EFI systems are somewhat more intelligent than Ford’s antiquated EEC-IV, but this needs attention. My advice is simple, this code is normally produced by a faulty engine temperature sensor or a…like my friend’s Merkur…a problem with the thermostat.

Instructions on removing the T-stat are here, and this suggests that 2006 models are plagued with T-stat problems. So perhaps it’s time for a new Thermostat, or perhaps you should re-install your thermostat and NOT RUIN YOUR MERKUR, SON!

 

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

]]>
http://www.thetruthaboutcars.com/2013/11/piston-slap-the-too-cool-miata/feed/ 57
Piston Slap: Cooling to the MAXX? http://www.thetruthaboutcars.com/2013/04/piston-slap-cooling-to-the-maxx/ http://www.thetruthaboutcars.com/2013/04/piston-slap-cooling-to-the-maxx/#comments Thu, 11 Apr 2013 11:00:38 +0000 http://www.thetruthaboutcars.com/?p=484313 Scott writes:

Hello -

Saw a Dex-cool question you posted previously, and figured I would try my own. We have a ’06 Malibu Maxx SS. Basically the car runs hot, but not all the time. I have been religious about flushing the cooling system and using only the correct fluids.

It has 91k, and I’ve read online that they tend to run a little above avg temp. Like your CTS questioner, this car was clearly driven hard before we bought it, but nothing horrible. It doesn’t throw any codes and doesn’t get into the red, but its definitely high according the gauge. On the highway it tends to sit right in the middle. If it sits in traffic it will rise a little, if I drive it hard it will shoot up but eventually come back down.

The water pump was recently replaced, but otherwise we have had no real problems with the car (aside from the usual crappy GM build quality, ISS, and lots of brake pads). I just ordered a new t-stat, figuring that was a cheap fix to try.

The car is paid off and I would like to keep it for a while, but I am worried putting my wife and daughter in this thing in the heat of summer, or going on a road trip, etc.

Sajeev answers:

So this Malibu was driven hard before you got it, but you’ve been good about respecting The Dex-Cool Monster…not letting the system get contaminated.  This means, depending on when you bought it, the previous owner coulda mixed fluids. And mildly gunked up the system.

See how being an Internet Automotive Mechanical Detective works?

More to the point,“if I drive it hard it will shoot up but eventually come back down” points to a partially clogged radiator. Partially clogged because of mild gunk accumulation.

When we’re talkin’ about a two-owner vehicle running Dex-Cool…well, I’m just being my typical snarky, untrustworthy self. No detective work there.  Radiators do go bad over time, failing more epically when sporting partially plastic construction too.  The water pump?  Not super-likely, unless the vehicle has plastic impellers (cough, VAG products) and they are crumbling to bits.  The electric cooling fans?  Probably not: they are merely less effective when pushing/pulling on a cloggy radiator…so the recovery time from hard driving is longer.

You can flush the radiator, or have a local shop do it for you. Or for added piece of mind: eliminate a known wear item on aging vehicles by spending all of $100-150 on a new one from an on-line parts vendor. I’d just order a new one and be done with it.

 

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

]]>
http://www.thetruthaboutcars.com/2013/04/piston-slap-cooling-to-the-maxx/feed/ 21
Piston Slap: Too Cool, or Dex-Cool? http://www.thetruthaboutcars.com/2012/08/piston-slap-dex-cool-or-just-too-cool/ http://www.thetruthaboutcars.com/2012/08/piston-slap-dex-cool-or-just-too-cool/#comments Mon, 06 Aug 2012 11:57:31 +0000 http://www.thetruthaboutcars.com/?p=455524  

 

Nate writes:

Ok, you asked for input and I’ve got a question about my 2003 Cadillac CTS. I figure I’m more likely to get a reliable answer from you and the best & brightest of TTAC than the goof balls at Car Talk (this letter is from February-SM), so I’ll ask.

I bought this CTS back in November. It had 135,000 miles on the odo, came from a private owner and apparently had significant engine work accomplished a year or so ago apparently as a result of a timing belt failure after it wasn’t replaced on schedule. Before being able to get the car licensed, I paid to have the thermostat and temp sensor replaced as I had a CEL and a P0128 code and the car wouldn’t pass inspection with a CEL code. The code came back after just about 1 week.

The CEL will clear if the ambient temps move up above 45-50 degrees but returns when the temps get back down to Utah normals for winter. I’ve been unable to find an online solution. I’ve considered installing a temporary partial radiator block, (cardboard & duct tape) to see if that old school fix brings the temp up. The car doesn’t have a temp gauge- thanks for nothing GM; but seems to warm up the cabin appropriately if not exceptionally fast.

Am I going to have to reset the codes each December before taking this in for emissions inspection or is there a real fix?

Sajeev answers:

Much like LSX swaps for people wanting to make a slow car fast, much like Panther Love for someone wanting a cheap and durable ride, I pretty much always think Dex-Cool is the problem when certain vintage GM products have temperature control problems.  As this paragraph shows, Dex-Cool is not my friend…and I am somewhat less goofy than the Car Talk peeps.

On the plus side, others are in your situation and they agree with me. Let’s face it: the timing belt proves that this car was neglected.  It’s a safe bet that Dex-Cool was never changed either, possibly topped off with non Dex-Cool compatible fluid too.  So there is a TON of the stuff you see in the photo below. And above. So I suspect that the 1 week grace period you mentioned was the time necessary to re-clog that temperature sensor and cause the P0128 to trip yet again.

I’d recommend a closer look at your cooling system, probably replacing the radiator too.   Just be careful how aggressively you remove Dex-Cool from the cooling system, you could flush it all out and get a ton of Dex-Cool “snot” stuck in the heater core. Which means you no longer have a heater. Which means…well, have fun removing the interior to get the heater core out. In a Utah winter. Damn, Son…

Sorry, I wish I saw another way out.  Maybe the B&B can help.

 

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

]]>
http://www.thetruthaboutcars.com/2012/08/piston-slap-dex-cool-or-just-too-cool/feed/ 22