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Coolant Air Lock


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Accord 2.2 i-CTDi
This week as i've newly purchased a Honda Accord 2.2 diesel, I decided to carry out a full service.

First thing on the list was a coolant change as that apparently hadnt been done in years. I followed the steps, albeit not entirely correctly, but then retraced my steps and did it exactly as the manual suggested.

Long story short... I'm left with what I believe to be as an air lock, more specifically in the heater matrix. I no longer get any hot air coming through.

I have tried:

- Leaving engine on for 15-20 mins on idle to get the temp up whilst leaving the coolant cap off.
- Running hot/cold air
- Squeezing coolant pipes
- Loosening coolant release valve on both the engine block and on the resevoir.

Is it time to take it to honda to do it again for me? Or is there anything else I could try?

I have only changed the coolant today, so could try letting the coolant work its way through the system on its own? Or will this damage anything?

Also, I believe I may have to resort to draining the whole coolant system again anyway as I didn't use genuine honda type 2 coolant. Which I have now ordered.

Let me know what the best course of action might be?



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Accord 2.2 i-DTEC
Are you sure its an air lock? Once engine in operating temperature try to set the temperature to HI, open all vents on dash and check if all are pushing just cold air or some are blowing hot as well.

I have the same problem after changing coolant, found out that the vent flap position motor stopped working for drivers side.