Quote:
Originally Posted by BMWX5CHI
So I recently replaced my expansion tank, along with various hoses. Now, I seem to have an issue with the heater. No hot air seems to come out of the vents. It blows semi warm air from drivers vent, and that's only for a few minutes. Won't blow warm through passenger vents at all. After a few minutes, it stops blowing warm air through drivers vent. What the hell is going on? It was working fine before my expansion tank started leaking. I bleed the system properly before anything.  I don't see what else could be causing this. Does anybody got any ideas to what could be causing the problem ? Used to blow hot air just fine.  |
Well it's possible there is still an air pocket in the heater core, since this was the last thing that was done it's the most likely culprit.
However, I had a similar thing happen after changing my coolant and it was the heater control vavle died. Apparently this fail with regularity on bmws just do a search and you'll find a ton of diy guides.
So assuming your system is fully bleed, Hester valve is okay, wiring is okay to the valve, then it could be a clogged hester core or failed controller for heating.
Btw, I replaced my heater valve with an eBay part and now the heat runs constantly. The part was labeled as compatible with an e70 but was the e60 heater controller and they are similar but not compatible replacements