Heater control is only blowing cold air..

[scotty]

Hey. When I had the car running in december/january the heater was blowing hot air, but it was kinda shibby, it only blew hot air in some settings etc. Now after 5 months(GTE swap) of being in the garage, it is not blowing hot air anymore, only cold.

Does anyone know what can be causing this?

Thanks,
Scott

 

[te72]

Possibly your actuator is sticking, this happened to me on occasion on my old 88. Try pushing up on the bottom of the metal rod of the actuator a few times and see if it unsticks itself.

 

[Jeff Lange]

It's likely the VSV that controls the opening/closing of the water valve. Try bypassing it and see if you get heat then, if you do, you'll need to replace the VSV, if not, start looking elsewhere.

Jeff

 

[scotty]

I moved the metal pin up and down, drove the car, when the engine was warm the pin was right up.. so that's not stuck. Still not blowing hot air though.

I suppose you mean this VSV(top left) Jeff? I'll try to see what happens if I bypass it.

Thanks

 

[mkiiichip]

If you bypass the vsv, hot coolant should constantly flow through the heater core. And you should have heat.

 

[ValgeKotkas]

You problem is probably in the Climate Control Unit On our Euro type units there are often cold junction problems. Take it off and look at the electrical schematics on the back (both plates).
For a LONG time I didn't know whats up (a week at -20*C suckkkkked...) till an electrician looked at it (I looked at it too before but couldn't notice those tinytiny cold junction problems )

 

[Dirgle]

Another thing to consider is if the car has ever had a BHG. If any of that headgasket sealant junk was used it will collect in the heater core and slowly diminish the heat produced. I purchased my car right after the previous owner did that, and it took me forever to figure out why I was getting less and less heat. When I finally pulled the heater core it was nearly clogged completely with the stuff.

 

[jetjock]

I moved the metal pin up and down, drove the car, when the engine was warm the pin was right up....

 

[destrux]

You did check your coolant, right? If the coolant is low the heat usually won't work, nothing to carry it through the heater core.