No heat

[jubbii]

Hello all,
I have no heatin my 1990 N/A. Ive changed the water pump, thermostat, radiator temp sensor and all hoses. the fan works (air comes out of all vents) pretty well. the car warms up fine temp gauge seems ok but no heat. Ive checked the heater core and it seems ok (no leaks). Is there a relay that i need to check?

 

[RoasT BeeF]

Did you check your coolant level? Might not hurt to flush the system if that hasnt been done in awhile too.

 

[GTM]

Originally posted by jubbii
Hello all,
I have no heatin my 1990 N/A.
...
Ive checked the heater core and it seems ok (no leaks). Is there a relay that i need to check?

No relay except for fans. Do check the coolant level first for these heaters are very hard to prime. Gosh you were so close when you checked the core, if you follow the hose which comes out of the thermostat housing and goes to the firewall. From inside the car look in that area for a metal fiting with hose clamps. You should see a valve with a lever and a solid wire Bowden cable attached. If it's disconnected just flip the lever and test the heater. Most frequent will be the clamp which holds the sheath in place will have come loose and instead of the lever moving the sheath will move. The other common problem is the wire will come off the lever, lastly the control mechanism is damaged. Sometimes the valve will corrode or get plugged inside which requires removal, clean or replacement. In an emergency you can bypass the valve and have how water circulating all the time or bypass the heater with a large double ended hose barb installed from under the hood.

Cheers,
GTM

 

[rcarrier]

Hey, i just ran into the same problem with my gsx, to make a long story short, my mechanic flushed the heater core, with some type of acid, now i finally got heat again,so thats a start if you havent already done that, just hope its not the heater core, You have to remove the whole dash
to get to it!!!

 

[BUCK]

It's probably the little plastic POS shaft & lever has freed itself from the cable from the Temp dial - It terminates at this heater core lever behind & above ECU. You can actually reach back there & flip it by hand from passenger side floor & get some heat if you are willing to pay the price - Or you can almost see it if you pull Temp & Duct Dials out of dash. PITA - you may be able to glue & thread a nut onto the shaft to keep the cable from jumping off.

BTW - these things circulate hot coolant thru the Heater core all the time - so they very seldom plug up - if they do you can reverse the heater hoses at firewall & they often un-plug themselves - This little flapper valve just lets the Hot air out or almost keeps it in (which is why you get warm air all the time - even when you don't want it).

 

[jubbii]

Thank you! I will try that and see what happens.

 

[Mike1992]

HELP I got no heat either, and only get air through the vents when i turn it full blast and its cold not hot

 

[BUCK]

It's probably the little plastic POS shaft & lever has freed itself from the cable from the Temp dial - It terminates at this heater core lever behind & above ECU. You can actually reach back there & flip it by hand from passenger side floor & get some heat if you are willing to pay the price - Or you can almost see it if you pull Temp & Duct Dials out of dash. PITA - you may be able to glue & thread a nut onto the shaft to keep the cable from jumping off.

 

[Mike1992]

thanks you were right!

 

[BUCK]

Great! - I put a lttle glue on a small steel nut & threaded it a little ways on the plastic shaft to retain the cable.