Boysenberry

Today my car (2002 ws6 Trans Am) popped the code P0128. At first, there seemed to be no issue, but I've noticed my stat has dropped several degrees. It normally runs at 205 and stays there, even when it's cold out. Today is a fairly nice day here in Missouri, nearly 50 degrees. I'm just wondering why my car threw this code and why the temp is dropping. Thanks!

ULTIMATEORANGESS

iTrader: (4)

how much did it drop?

LS6427

iTrader: (2)

I don't see PO128 as a code.

What did the description say on the scan tool?

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_JB_

iTrader: (33)

I had the same code when I first got my car years ago. The previous owner put a cooler thermostat and didn't adjust the computer for it. I replaced it with a stock one and the issue went away and has never came back.

Since your car just started this, I bet its a fail-safe thermostat and has failed, and needs replaced.

_JB_

iTrader: (33)

It will say something like, "coolant temperature below threshold."

Boysenberry

JB is right, it said something along those lines. I continued to drive the car because it never dropped too low, it only dropped a total of maybe 20 or 30 degrees, still driveable. But as I was driving, the engine light turned off and the stat went back up to normal. Scanned it, and no codes were shown.

I read somewhere else on here that this code often randomly pops up for no reason and will cause your stat to stop working, which might have been why it seemed to be dropping. As far as I know, there was never a problem in the first place. I couldn't seem to find one, anyway. Took it to the drag strip today and had no problems all day. Ran flawlessly. So Idk

_JB_

iTrader: (33)

Mine only popped up a few times, only during the early spring days where it was like 40-50*F outside and I immediately jumped on the highway. I didn't change mine until I did a coolant flush as it isn't a big deal.

Boysenberry

That's about what the temperature was when mine popped up. I'm not too worried about it after finding some more posts about it on here, sounds like it's just kind of a flaw in the computer more than anything rather than an actual problem with the cooling of the engine.

LS6427

iTrader: (2)

When you guys say "stat".....are you guys referring to the Thermostat.....?

Or the temp gauge?

When you say things like

.....but I've noticed my stat has dropped several degrees.

And

.....randomly pops up for no reason and will cause your stat to stop working



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