Baron009

It's been years since I posted here. Back in 2008 I bought a BMW 135i and the intention was to sell the 944. Well that never happened! I ended up storing the 944 since then, driving it on the rare occasion. Now I'm planning on bringing her out more often. I just had my timing belt and water pump done and I thought I was good to go! Except now my heater is on ALL the time - I'm being roasted alive! (there's some terrible joke about Germans and ovens in there...)

Anyway, I can't seem to figure out what's going on. I checked the damper (picture below) and the clip is attached, but it seems like it might be seized. I assume when you play with the temperature control **** on the center console it is supposed to move this damper?? Or am I way off here? Anyway this is what it looks like. Should I be checking somewhere else as well?


Clip seems fine...

Thanks!

Mike

Baron009

Ok, so I was poking around a bit more - online and in the footwell...

I have read that you can tape or ty-rap the rod back so that it only blows outside air as a temporary fix. Does anyone have any pictures on how to do this?

mel_t_vin

On the firewall behind the heater valve assembly, above the supply/return coolant hoses to the heater core, there are two small 3mm metal vacuum nipples. The upper one is the main vacuum supply to the entire hvac system and the lower one is the vacuum supply to the actual heater valve. Make sure these vacuum lines are connected and in good condition.

If I recall correctly, vacuum at the heater valve closes it and prevents circulation to/from the core. Vacuum also positions all the mixing/directing flaps.

konakat

The nipple for the heater valve is actually plastic, and it is notorious for breaking. There is a thread somewhere around here about a metal heater valve from an Audi that is a direct replacement.