View Full Version : 94 base model no heat any ideas?
fastrf
01-27-2012, 02:25 AM
I have no heat but temp reads fine. It has been that way since i did the heads. I think it is in the internal controls but dont know wht would go bad or where to start????:eh:
Boost4VR4
01-27-2012, 09:27 AM
Heater core issues most likely...
green-lantern
01-27-2012, 10:09 AM
Ether the coolant isn't reaching the heater core (hoses bypassed when you did the heads) maybe the hoses got mixed up, or the flap that changes the air route through the core isn't working. Some cars won’t get heat if the coolant is low but IDK if that could be the case on these cars, the core is pretty low.
Is it even blowing air?
n2nsanity
01-27-2012, 05:54 PM
that flap greenlantern is talking about is the blend door and i'd say is the most likely cause
they break easily in most cars although i've never seen a broken one in a 3/s
could also be the cable came off the blend door under the dash
when you turn the hot/cold knob, do you hear a thump type sound? (this would indicate cable is attached and door is opening/closing)
or do you have digital climate control?
i think having hoses backwards could slow down flow through the heater core, but shouldn't stop it all together
if it's bypassed, that would be too obvious, but i'm sure it's been overlooked before
could also be a blockage in the heater core
not fun getting that out but you can test it and clean it easily
hit it with lightly with air compressor on the in line and make sure coolant comes out the out line
other than that, look at what else would affect coolant flow (thermostat, water pump, etc)
green-lantern
01-27-2012, 06:16 PM
that flap greenlantern is talking about is the blend door
lol thanks, I have no idea what they call that damn thing.
Alex3000gt
01-27-2012, 07:55 PM
With the car cooled down, peer down into the radiator cap. Are you topped off? Did you get all of the air out of the system after doing your heads?
After draining coolant, I usually run the car up to operating temp with the cap off and slowly add coolant as it needs it. Maybe someone else has a better way of getting all of the air out.
Beyond that, check the door on your HVAC unit like people here were mentioning. Can you feel the HVAC unit (plastic box behind the radio) get hot once you are at operating temp? If you feel heat coming off of the HVAC box, and lukewarm air is coming out of the vents then likely the flapper door is not functioning.
fastrf
01-27-2012, 09:35 PM
thanks yes i get air i think it is flap also havent felt the box behind radio yet but deff on my to do list
n2nsanity
02-03-2012, 02:24 AM
if it's not the blend door, look more into flushing the heater core, and again be cautious with the psi
good reference:
The heater core took a crap. Literally... - 3000GT/Stealth International Message Center (http://www.3si.org/forum/f1/heater-core-took-crap-literally-531560/)
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