You are here:

Pontiac Repair/no heat in Pontiac Montana


I still have issue with no heat...I checked the coolant level in both rad and overflow and all OK...cabin filter is clear

Hi Ray:

try this when you go from full hot to full cold do you hear and or feel the air flow change somewhat? if so the tempature doo is working and then it is a matter of a issue with coolant flow into the heater core. if you do not hear the air flow change it's a HVAC door issue either a broken door or a bad actuator for the door.  if it's a flow issue with the coolant it could be a plugged heater core due to dirty coolant or a thermostat that is opening too soon aor stuck open and the flow is too fast though the cooling system and it's not absorbing the heat from the engine. does the temp gauge read in the normal range when it's not heating? does this van have rear HAVC if so do you have heat out of the rear unit? one last thing to do is to take the heater hoses off at the back of the engine and use a garden hose and flush the hoses in one direction and then back in the other direction to dislodge any debris that may have collected in the heater core. it act like a filter is there is dirt and debris in the system the passages are smaller then in the radiator so it's prone to get plugged up. good luck :-)

Pontiac Repair

All Answers

Answers by Expert:

Ask Experts


Todd Puccio


General auto repair,electrical issues,driveability issues,anti-lock brakes,SIR systems,HVAC,engine performance,Gm specific. I have worked at my current dealership since the 1990 model year anything much older than that I have limited exposure to. I do not have very much transmission experience so those question you may want to ask of another expert. When you send me a question let me know the exact make/model/engine and year for the car or suv you have it makes it easier to answer the questions that way. If your happy with the answer I gave you please feel free to Donate. This is a free service to you and I am not compensated at all by this web site. I have 22 years of experience to share with you and my knowledge wasn't free to me. I had to pay for my education.


Experience in the area: I have been a technician in GM dealerships for over 22 years and I am a ASE master technician. I work at a Buick and GMC truck store Previously I worked at a Pontiac GMC store for 18 years. I Served a a lead technician when dealership was on a team system. I just recently moved to a Buick,Hummer,Saab Store when my franchise was purchased by this dealership. Organizations: ASE master technician


Education/Credentials:High school diploma,2 year vocational school degree 2 year college degree. Associates degree in applied sciences (auto technology)Awards and Honors: GMC master technician

Awards and Honors
Master GMC truck technician Master ASE technician in 9 categories

©2017 All rights reserved.