my sunbird have no heat HELP

[steve1820022000]

i have a 1991 sunbird and i have heat and it dosent blow inside the car the blower motor fine and the heater core fine whne you flip the blower switch all the way up it blows but dont know where to someone told me something about a resitor anyone know any thing about that if you can help me leave me a message here or e mail me at [email protected]

[89Sunbird]

Sounds like something in the HVAC unit might be broken...easiest fix is to find another at the junkyard and swap them out...pretty easy procedure...

[richtazz]

The blower resistors rarely failed in the 87-94 Cavi's and Sunbirds (unlike the 95-up's which are very common). If the air is not switching from floor/vent/defrost, it could be a cracked/disconnected vacuum line coming from the engine through the firewall, as the mode actuators are vacuum operated.

[89Sunbird]

He doesnt mention anything about which vents it comes out of, but says the speed switch doesnt work right.

I was thinking about the hoses as well, but it sounds like his adjustable switch isnt working in the middle settings...which sounds more mechanical than vacuum related...

[richtazz]

He said that he hears the motor running, just can't figure out where the air is going. That's what made me think it was a mode issue, not a blower speed issue.

[89Sunbird]

Perhaps a blockage in the plumbing?

[clutch492]

You will find that the heater core is covered with a film of dirt and what looks like mold that has grown on the face of the heater core.

Remove the blower motor and reach in the heater box. Scrape as much of the crap off as you can with your fingers. vacuum it out and then blow the heater core with a blow nozzle that has an angled blow-tip on it. This will get the air to start coming out of the vents again.

I have had 2 of these cars and they both have had this problem.

Clutch492
Kevin
Kansas

[lilevo]

My girlfriend has a 2.0L 91 Sunbird. Recently in the morning when it is fairly cold outside < 40*, the heat will not blow on any setting.

Later in the afternoon when things warm up, everything works normally at all fan speeds.

Any ideas?

[avengere1]

i have a 1994 sundird with a 3.1 ,i just replaced the heater core and since replacing the heater core,the blower motor runs fine when the engine is cold,when the engine warms up and i turn the blower of and back on again it wont restart,but if i let the car sit till the engine is cold the blower works again,please help fustrated??