Weird heater thing.

94 Rodeo V-6 4wd, auto.

Heater goes cold when idling or stopped at a light. Heater warms up again right away when I start going or rev the engine. I havn't looked at it yet, so I wanted to ask to see if anyone knew what the problem is. Engine temp stays constant thru all this.

Anyone?

search for radiator.

There were some recent posts (past two months) about this, I think.

I saw this over on another forum, it sounds like your problem:

"My 94 Passport (145,000 miles, 3.2, auto) is having trouble with the heater. It works great as long as it's driving down the road or revved up, but about 5 seconds after I pull up to a stop light, or sit idling somewhere, it starts blowing cold air. I added a little antifreeze about a month ago, and it still stays at the right level in the resevoir. I also noticed this summer when we had some 90 degree F days and I was running the AC, that when I would idle after the truck was good and warmed up, the temp gague would climb up into the red. Any ideas?"

Answer:

"Hey Doug- When it is cold, remove the radiator cap and check the coolant level in the radiator. It acts like it is low. If it is the cap may be leaking and not drawing coolant from the resirvoir. Good luck Joe".

Reply:

"Yup, that fixed it.
Thanks for the Help!"


Good luck,
Dale

Hmmm, a leaky cap would be easier to fix than digging into the heater control systems. :cwm27:

Thanks!