Check Engine Code p0128
 

2002 Bonne 130,000+ miles. Original Stock Tstat.

I guess from what I can gather on here that this code is generally fixed by installing a new Tstat correct? I have already replaced the temp/coolant sending unit.

Is a factory 195 tstat fine or should a guy go aftermarket with a 180? If so, someone have a good site or part number to purchase?

Anything else that this code sometimes points to?

DTC P0128 Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature

Tsat is the most likely culprit. Does the 2002 have two temperature sending units?

Should be only one two elements in it. One for the PCM, one for the gauge.

I just got that code too, is it possibly cause I have a 180 and with it being so cold its just not getting up to temp the pcm wants.

For future reference what year did they go to a single unit?

Should be all Series 2. But even the 95 Buick Riv L67 (Series 1) had a dual-element single sensor, and the other LIM sensor hole has a brass plug.

My drilled 180 took me through all of last winter without an issue. This year, it's already throwing that code...even after I put the sight shield back on. Looks like I'll be swapping out to the 195 for the winter.