awilli6

Just drove my 89S4 for about 50 miles. During the drive the heat did not get hot. I drove it about a week ago and didn’t have a problem. The PO removed the front air louvers from the front. It’s cold outside. Will the cold air hitting the radiator directly keep the heat from working? What are your thoughts on why there’s no heat.

Ladybug83

Relay?

awilli6

The blower works, just not getting hot. I did know there was a relay for heat. Which relay are you referring to?

Bill Ball

What did your water temperature gauge show? The louvers primarily affect warm up time. If the water temperature moved off the low end even a little, you should have heat. I would check the heater control valve. Somebody may have disconnected the actuating lever and wired it shut because it leaked heat into the cabin in the summer. Also, it's possible the controller for the mixing door is not working and the door will not move properly. If it is the latter, this thread will help:
https://rennlist.com/forums/928-foru...r-testing.html

Ladybug83

It was just a guess, wasn't sure if the flaps were controlled through a relay or fuse. Disregard

awilli6

Thanks Bill. The temp gauge went to normal operating temp. I changed the heater control valve months ago. It’s not wired shut. I’ll try the other suggestion.