P0128 code

2006 CHEVROLET MALIBU

100,000 MILES • 2.2L • 4 CYL • 2WD • AUTOMATIC

AARONMAN

MEMBER
3 POSTS

I have a P0128 code. I have changed out the thermostat and engine coolant temperature sensor. The engine still has trouble getting to operating temperature. The coolant level is filled and the fans are not stuck on. when the heater is on it blows medium warm air.

Mar 28, 2019 at 1:41 PM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

Good evening,

What temperature thermostat and what brand did you use?

Roy

Mar 28, 2019 at 3:15 PM

AARONMAN

MEMBER
3 POSTS

I believe it was the fail safe brand from AutoZone. It is set to 180 degree. After you asked I read the reviews on AutoZone's website and it had 1 star with 5 reviews. Can a thermostat go bad after a few weeks?

Mar 28, 2019 at 3:22 PM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

The fail-safe thermostats are junk.

You cannot use that type of thermostat. Besides, you need the OEM thermostat of 195 degrees. That is not an option and that's why the light is on.

Roy

Mar 28, 2019 at 3:25 PM

AARONMAN

MEMBER
3 POSTS

Thanks what brand do you recommend? Any OEM brand?

Mar 28, 2019 at 3:28 PM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

Stant is a good brand.

Make sure you get the correct temperature and not a fail-safe unit.

Roy

Mar 28, 2019 at 3:31 PM

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