1991 Chevy Cheyenne Heater quit working

GEAUXTIGERS

MEMBER
1991 CHEVROLET CHEYENNE
6 CYL
2WD
AUTOMATIC
144,000 MILES

The heater in my 1991 Chevy Cheyenne pickup, 4.3L engine quit working last night. I noticed the temperature gauge running hotter than normal and then noticed the heater was blowing cool air. There is no a/c in the truck, just heat. Once I turned the heater off, the temperature returned to normal. Turned it back on and had hot air for a couple of minutes and then cool air and the temperature gauge began rising again.

I guess the first place to start would be the thermostat but if it was bad woudn't I have problems without the heater being involved? Any advice is appreciated. Thanks.

3 Replies

RASMATAZ

MECHANIC
75,992 POSTS

You're on the right track with the thermostat get that replaced and comeback for further assistance.

Was this

answer

helpful?

Yes

No

+1

Wednesday, January 2nd, 2008 AT 5:34 PM

GEAUXTIGERS

MEMBER
20 POSTS

Okay, now I feel really stupid! I checked the radiator (should have been my first act) and I have no coolant in either the radiator or the reservoir. Don't really use the truck that often, mainly for driving back and forth to hunting camp. Admittedly, I last checked the coolant a few weeks ago.

I obviously have a coolant leak somewhere. I will fill with coolant and check for leaks.

I'm counting myself lucky it didn't overheat last night! No water in the oil so appears not to be any major damage.

Thanks for the help and quick response!

P.S. I will still change the thermostat - too easy to change and too cheap to ignore.