[Schurkey]

Originally Posted by STEELCITYFIREBIRD

When driving down the road I have 120*+ from the vents.

Yeah, I'd be peeved at lack-of-heat, too. If my heater was that cold, I'd suspect a failed thermostat.

My heaters typically run 160-170-ish. Depends some on inlet air temperature, and of course on thermostat rating.

If this were in MY driveway, I'd have an excuse to buy one of those vacuum-refilling cooling system tools. (Airlift or similar product.)

https://www.uview.com/index.cfm?dsp=...productid=5120

https://www.youtube.com/watch?v=mdFxiz8skaQ

The other hateful alternative is that you've got a failed head gasket or cracked casting that's putting a steady stream of combustion gasses into the cooling system.