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no rear heat/no foot heat

3K views 7 replies 8 participants last post by  Leeann_93 
#1 ·
sooooo....after much reading and help from yall....i think i've got my oil adapter leak fixed....yall are vaaantastic!!!

now onto the next issue

no rear heat at all only cold air blows, no footwell heat, but it blows into the underside of dash in the black "ductwork" in passenger footwell just not out of the vent at all. Defrost blows strong but the blower motor hums differently in defrost.

so after alot of reading i will start with:
1. "No heat/air/vent control issues? Start here GenII" thread - started reading this and looks like i need to trace some vaccuum lines
2. flush the coolant...probably good idea since i bought it used and don't know if this has been done...coolant looks green
3. bypass the heater control valve to see if i get rear heat

i do have very hot heat from dash vents, but it does cut out occasionally and blow warm for a second (maybe when i hit a bump in the road)

i shall continue researching for now.....any other advice?....point me to any certain thread on this?

thanks guys and girls
 
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#2 ·
I have no experience with the problem you are having with the front, but have also read it's a vacuum line. The rear however I have fixed. I would bet at least one whole dollar that it is the heater control valve. Easy to check. Take the vacuum line off the top of it (from the car) and put it on the bottom fitting. I'd bet you start having rear heat.
 

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#4 ·
bill-e-boy said:
...coolant looks green
That is perhaps the single best finding one could discover in a used car.

I would do what WoodyButch suggests and just replace those darn vacuum lines. All of them. Inexpensive, simple, tools required are a pair of scissors and maybe a pair of pliers.

When your vacuum is goofed up EVERYTHING is goofed up. And it's just plain simpler to replace everything than it is to try and Sherlock Holmes it down to where the bad hose is.

Lump
 
#8 ·
Do you have the optional rear heat (vents on the driver's side beside the 2nd and 3rd row benches) or are you looking for heat to come out of the little floor vents behind the driver and passenger seats?

If the latter, you're missing the diverter piece under the glove box/cupholder bit.

If the former, you need to remove one phillips head screw (open the driver's door, remove the screw near the seatbelt, slip the seatbelt through its escape route then pull the cover off the side bin, one snappy thing at a time) and check the rear heater core and blower motor.


If they check out okay, pull the gauge cluster surround and check the actual 'rear heat' switch. If that checks out okay, then check out the heater valve thingy as posted by Jay above. If you open your hood, find the 2 lines that go to/from the heater core on the passenger side. Follow them to the plastic valve. Make sure the vacuum line to the valve is good from end to end, then I'd suspect the valve itself. You either can remove the valve entirely or replace it (just make sure you get the one for rear heat as it has 2 more connections than the one for front heat only).
 
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