Hey Guys,

My tahoe is giving me another issue. The heat isn't working in the front, but works fine in the back. They both blow air, but the front is cold and the back is hot. Any ideas? Thanks. Tim

 

i had the same problem on my sierra all i had to do was cut the heater lines and blow compressed air through each side mine had all kinds of junk in it i had to do this 2 or 3 timesi just poored water down the outlet tube and kept blowing it out

 

are you talking about the heater core coolant lines? I'll have to try that. How come this stuff doesn't happen in any other season? Cold winter weather isn't my favorite to work in.

 

try what tall n turboed said but i think it's an electrical issue if one blows hot and one cold. my vote goes to the a/c controller

 

my escy does the same thing but opposite,duh.lol.hot in the front but cold in the bavk ,ide like to find out also.

 

what year tahoe? my 03 had an issue where the rear heat, and the passenger side heat were blowing hot, but the drivers side cold, i did some digging around and found that the servo that controls the heat mixing on the drivers side had hung up and did not reset when the truck was started up. try switching the controls to cold, then shut the truck off, wait a minute, start it back up and then switch the controls back to hot. this worked for me. but if you have one of the newer, nicer than my base model, with the digital controls, it might not help.

 

Search this section for "blend door actuator" or "servo" or "motor" and you should find a bunch of info about guys with similar concerns. There's a "re-park procedure" that you can try first...search this section for those words and you should find that too

 

the reason his heat in the back works is because there are two seperate heater cores one in the front and one in the rear assembly i found both of the cores on line the rear is a little tougher to findbut heres the links for both incase blowing the core out doesnt work

rear..... http://www.theautopartsshop.com/Sear...ahoe%2FFS93057

front..... http://www.theautopartsshop.com/Sear...nd+PartDetails

 

I just stumbled upon the rear heater core. I followed the lines that tee'd off from the front core lines. I ended up doing the relearn or repark that I heard of. I figured, whether it works or not, you only have to disconnect a battery terminal. After just doing that, the heater is back to working properly.

Thanks for all the input everybody.

 

glad to see you got it back to normal.