Recently replaced my thermostat in my 1997 M3 (US spec) and everything has gone smoothly, no leaks from housing, car holding temperature fine, etc. Now the issue is when I bleed the coolant, the air from the vents is not hot unless I press the throttle and raise it to about 1500RPM. I also notice the coolant level in the expansion tank starts to drop a little. Then when I take my foot off the throttle the air eventually goes back to not hot and the coolant level starts to creep back up to where it was before. What could be causing this? I raise the front end of the car when bleeding the coolant, have bleeder screw and fill cap off, have HVAC sent to 90F full blower speed. Is this a broken heater control valve or something else?
I will mention that I've tried bleeding the car a few times now. It drives fine and holds temperature. But every time I turn the car off I get a coolant level low warning on the OBC and when I check the coolant level it has dropped to almost the bottom of the expansion tank. Then when I turn the car off it rises back to around the KALT/COLD line. Not sure if this is part of the same issue or not. Any insight or advice is much appreciated Thanks in advance!
I will mention that I've tried bleeding the car a few times now. It drives fine and holds temperature. But every time I turn the car off I get a coolant level low warning on the OBC and when I check the coolant level it has dropped to almost the bottom of the expansion tank. Then when I turn the car off it rises back to around the KALT/COLD line. Not sure if this is part of the same issue or not. Any insight or advice is much appreciated Thanks in advance!