Thermostat and CEL P0128

[simmer9000]

I got a P0128 check engine code from my scanner.. According to the manual it's a failure to reach the correct engine temp for coolant. Could be a fan on too frequently or a faulty thermostat.Light came on at 67,000 km on a 2003 GT.Went to a Pontiac dealer and part was almost $50 with gasket... went to Toyota and the exact same part was $27. Fit perfect and was identical to the one I pulled out.The http://www.matrixrides.com/Rep...1.pdf link was awesome... as are all the pdfs you can get on the site. All I can say is look out for trying to get the freaking alternator back on... b**ch to get back on and aligned. Bottom line is the cel light was reset my my scanner and has not come on in 1000 kms, so it was the tstat.Small engine cavity though... your need really small hands.

[fawlty04]

dude, weird. mine also randomly came on at 65000 miles. glad to know this won't cost me an arm and a leg. i just failed my smog check cuz of this little beast. grrr...once again, thank god for generation vibe. -heatherp.s. so how much is one of the scanner doohickeys? very seductive gadget.

[joatmon]

Hi Heather, welcome to genvibe.The matrixrides site that simmer9000 referenced unfortunately has gone AWOL. The file linked dto was one of the PDFs in the softcopy of the 03 Matrix manual, which can be downloaded from a link in http://forums.genvibe.com/zerothread?id=1156JohnC wrote up a nice how-to on thermostat replacement, see http://forums.genvibe.com/zerothread?id=23818 for the link to it.Some of us have bought a tool called a "scangauge". There's a scangauge discussion thread at http://forums.genvibe.com/zerothread?id=20577. I used mine to view and clear a pesky P0420 that turned out to be my catalytic converter, now I mostly use it as a trip computer to help me eek out an extra mpg or two.

[ToolGuy]

Heck yeah the alternator was a B to get re-aligned! I was so mad, I wrench on all my cars and this one was a PITA! I was ticked off that day!

[ToolGuy]

Quote, originally posted by fawlty04 »p.s. so how much is one of the scanner doohickeys? very seductive gadget.My company owns this company now but you can buy the products at most auto stores. Here is a link on the types of inexpensive scanners...http://www.actron.com/

[fawlty04]

sadly it's also the cracked exhaust manifold that needs fixing -- at least that's what the dealer has told me.... guess i'll be getting a second opinion, but DUDES, total bummer.

[fawlty04]

interesting memory -- i just had the coolant changed out at 56,400 miles.so there totally should not be an issue with this, yeah? could this code come up if i accidentally, erm, left the engine filter top un-clipped when i cleaned out the filter? i've since relatched it, and the light has gone back off... do i need to concern myself with the thermostat anymore?

[damronjr]

I got my OBDII code reader for $40 from Harbor Freight. Don't know what you have out there, but try to find one or just take it to any Autozone and have them read/look up/clear your codes for you for free!

[fawlty04]

right on. thanks for the heads up! autozone is my new hero

[simmer9000]

My scanner was 120 canadian at walmart.Too bad about the Matrixride site. Hope someone at least keeps an active link to the pdf's. they are amazing as a reference.

[simmer9000]

if you left your lid off it could trigger one one the sensors, and once fixed, it would turn off the CEL after a few cycles if the engine was back to operating normally, so that's normal.