1998 Cadillac Eldorado heat won't blow hot

heater blows luke warm, wont blow hot, both heater core hoses are hot, what do i need to check?

The air blend door is likely not closing towards the heat and letting cool air past. On a 20 year old car, the sealing foam on the door is probably gone. It may be the actuator has failed for the blend door. Check that first. It is under-dash, not sure where on this model.

If it isn’t the actuator, the door itself may be stuck or not sealing. Not sure how you gain access to it but it will NOT be a fun job. Lots of stuff needs to be removed from the dash to access it, more to fix it.

GM hvac actuators are a pretty common complaint. I expect that’s what the problem is. The good news is that the actuator that tends to fail is the one easiest to replace. Sometimes the actuators don’t fail, but just get confused and need to be reset to their home positions. That’s where I’d start if I had that problem. Any shop with a GM scan tool can do that for you.



thanks for the info, beings im a retired body man ive had them dashes tore
down to nutin, replacing passenger side air bags, so im not scared of the
work plus i have a Cadillac factory repair manual. Car sat for awhile so
your probably right, i know its getting vacuum.