I just picked up a odbii scanner because this is the second time I've got a SES light in the past month..

Well I'm getting the P0128 Coolant Temp Below Thermostat Regulating Temp...

I've got a ralliart 71c thermostat and I'm assuming this is the problem.. is anyone else experiencing this?

Is there a fix out?

 

dont they recommend only using that during high temperatures? cant imagine itd be that warm in w.virginia.

 

Yeah it's kind of cold here but spring is right around the corner. I always let the car warm up before driving it. It's just weird that it came on today with it being warmer than it has been.

 

my guess would be that 'MAYBE' you didnt let it warm up enough. i dunno tho ...maybe your cars just anxious for the warmer weather so its acting up.

 

I dunno.. I think it will go away once it warms up.. Last night it was well below 0 and today it was around 40f or so. I'm just glad it wasn't a p0300 or something like that

 

I have the same thermostat, and i live in PA. But i never had that code before. Its been in for like over a year and its gotta be colder here then w. virginia

 

I had the same issue when it was cold here. Basically the only fix is the switch the thermostat back to the stock when it is cold.


bryan

 

Glad to see I'm not alone then. Spring should be here soon enough.. so I'll leave it in there for now

 

I had to remove mine also. Engine always thought it was cold and ran really rich. I switched back to stcok, no problems.
This happened here in the AZ desert in the summer heat (110-120F).

 

I wonder if someone could come up with some sort of ECU flash to compensate. I don't notice mine running any more rich than normal but a lot of time it idles at around 1200 or so.. kind of annoying

 

I ran into this issue the past few days! Same OBD code probably due to the Ralliart Thermostat! Is there any fix to this? Perhaps lower the temp somewhere with ECuFlash?

 

My car is flashing this code this morning as well too...Very weird. It was very cold out and I was just driving it easy peasy to break things in since its been on stands for a while...Winter is almost here!