Heater Question

[muddywaters]

Hi, Is there/where is the heater core shut off valve for a/c mode, my a/c quit and seems to be excessive heat coming from ports on my 88, it has the auto climate control and it's Greek to me. And I mean that in a mysterious way.........

 

[fatboyreyn]

heater core valve

Hi, Is there/where is the heater core shut off valve for a/c mode, my a/c quit and seems to be excessive heat coming from ports on my 88, it has the auto climate control and it's Greek to me. And I mean that in a mysterious way.........

There is an actuator valve on the heater box under the dash, which controls the flapper to direct air to a particular vent. This is vacuum controlled by the program controller located under the drivers dash. The program controller is a row of solenoids on a circuit board that is told what to do by the climate control unit in the dash. There is also a vacuum valve on the hose under the hood that feeds the heater core. you can unhook the vacuum line, plug it, and hold the valve in the closed position, so no antifreeze will flow through the heater core. I just got my system working on my 86, after much reading and repairing of the above metioned componets.

 

[muddywaters]

Thanks for the info, my problem is I can't locate the vac. valve under the hood, I know what they look like, my 88 has the oil cooler on it and I thought maybe they relocated the valve, but I can't find it...................