A.c. off due to engine temp. Code p0128 comes out. Replaced leaky thermostat. 6months later code came back. Replaced ECT sensor. 2 weeks later same code. Any ideas?

 

Did the code go away after you replaced the sensor? If so, probably a bad or cheap sensor. I tried replacing one on my lumina awhile back, lasted about 3 days (10 bucks from Amazon), So I bought the $50 sensor from autozone.

 

• I actually got the one from auto zone too. After I replaced the ect sensor and erased the codes, another code came on, P0116 and P0117 or P0115, but they too disappeared after I turned the car on so I assumed all was well. A week later this original code (P0128) came back on and the check engine light too. Same routine, a.c. off engine too hot despite being 50 degrees out. Coolant level about half. Thought better of filling but at this point willing to try anything. Still love and promote Chevy though.

 

Coolant level at half, is that in the external tank? Might not be the engine is hot, have you replaced the tstat since the last time 6 months ago?

 

Have not replaced the thermostat. Cost me almost a hundred. I heard thermostats will sometimes will become stuck in the open positions but don't know if that applies to my type seeing as how the housing is part of the thermostat. Will check when I can this weekend. Also heard maf sensor sometimes causes a p0128