Hi guys I just bought my fiance a 1999 2dr blazer with the 4.3l. It is her first car. Anyway when we were on our way home we tried to use the heater no heat. So i read some of the post from here and tried a few things that you all have posted. I just flushed the heater core out with a garden hose and a bunch of crud came out. It seemed to work but i have to stay on the throttle to get heat inside. If I let the motor idle the motor runs hot with no heat inside. While i am driving it is fine both the temp of motor and heater. Any suggestions I would greatly appreciate it. This is just another problem we are having after just losing our home do to the hurricane.

 

Sounds like you haven't worked all of the air bubbles out of the system yet. Keep track of it and make sure that the radiator and the overflow tank are both full. It may take awhile to get the system entirely free of air...

 

Ok i will go check that. Thanks for the info.

 

I just fixed a heater prob. with my 2000 blazer today. Flushed the hoses and core. Just a little gunk but not much came out. I also replaced the thermostat and changed the coolant. Well my heater now works. I think the thermostat was sticking but who knows. Like I said my heater now works and I am happy. I want to thanks everyone who has posted on this subject before as it helped me out big time.

 

Well I am still having problems with mine[:@]. Today it ran hot while I was driving,but then it cooled down and ran right under 210 Degrees. I dont know what to do next.I still need to be on the throttle to get heat inside.If anyone has any suggestions I would appreciate it.Thanks