Heater doesnt work!!!

[85.5classic]

My heater doesnt work, and when I turn on my air it stays on full blast whether i have it one high or low....What could it be?

[Lawrence Coppari]

Could be a number of things from a broken thermostat to a sticking control valve just in front of the firewall. The control valve regulates the amount of water from the block to the coil in the dash. I would suggest you start the car, make a mental note of position of arm on valve, change heater position and see it it moves. Check fuses and relays. I think vacuum controls the valve. Can't remember as I have not looked at mine in a while.

[85.5classic]

thanks, ill check that out!