Heater not working well engine fan runs even after engine is off

HAPPENING88

MEMBER
2004 HONDA ACCORD
3.0L
V6
2WD
AUTOMATIC
125,000 MILES

I have the car listed above it is the EXL model. I recently replaced my radiator and the problem started shortly after. I recently got check engine light and it showed code p0128 for coolant thermostat.

My car has issues with heating. The heater works but noticed it takes a lot of time to heat and I can feel warm air intermittently and it starts and stops blowing warm air and then blows cool air.

I also noticed that at times I would notice one of the heater fan running a minute or so after I turn off engine. It does it even if I drive short distance and in cold weather. I know my coolant is not leaking.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
47,690 POSTS

Hello,

I think the code is telling us the thermostat is stuck open which will cause the code and the heater not to work. Here is a guide to show you what you are in for when changing the thermostat out. I would replace the thermostat and clear the codes.

https://www.2carpros.com/articles/replace-thermostat

Here is how it is done on your car (below)

Check out the diagrams (Below)

Let us know what happens and please upload pictures or videos of the problem.

Cheers, Ken

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