Please help, not getting heat!! 93 LS400
10-19-11, 06:12 AM
#1
Driver School Candidate
Thread Starter
Please help, not getting heat!! 93 LS400
So I have Googled and trolled and seem to have tried everything but no luck. Changed thermostat, burped and come to find that the wire to the Heater Control Valve is not moving. Pulled cable off and manually moved lever, after wiggling it a bit, it seem to have broke free and moved higher and I was able to feel a bit of heat. This morning, thinking I would have a little heat, I got nothing but cold air again. I'm not sure how high lever actually goes. Would someone mind posting a shot of yours so I can compare? On a bad note, as I played with temp settings, wire did not move up or down. A/C works fine but no heat. Heat was working awesome when I purchased the car back in February this year. I am in no way a mechanic but I do have the know how to replace whats broken. At this point I'm not sure whats broken. I am going to look into the room temperature sensor later today if time forbids as well as a possible kink in cable behind dash this weekend.
Does it suppose to go higher?
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By vudugan at 2011-10-18[/IMG]
Does it suppose to go higher?
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By vudugan at 2011-10-18[/IMG]
10-19-11, 07:58 AM
#2
Pole Position
First, welcome to CL. You're not gonna be able to move that cable by hand, it works electronically on a servo motor located on the bottom of the heater assembly. (under dash, behind radio area) That servo motor might be shot but I'm not 100% on that. This heater system is very complex and weird. Mine wasn't working for two winters but my heater core was also shot so I didn't have heat anyway. When I changed my heater core I completely forgot to check and/or repair that motor or cable. Luckily, that cable mysteriously started working again when I was done.
In that pic, that's as high as the valve goes. You might still have air in the coolant system. Do you have heat when you drive or at higher RPMs? If so, you have air bubbles. When you bleed the system, fill it up, get the engine to normal operating temp, open the heater valve by hand, (seeing how it doesn't open when heat is on max) and loosen the 17mm bolt on top of the thermostat housing. (just a little) Some coolant will come out when you do this. Just crack it so you can see the air bubbles through the coolant that spills out. If no coolant comes out then you don't have enough coolant in the system, which will cause you to have no heat. Let us know how you make out with it.
In that pic, that's as high as the valve goes. You might still have air in the coolant system. Do you have heat when you drive or at higher RPMs? If so, you have air bubbles. When you bleed the system, fill it up, get the engine to normal operating temp, open the heater valve by hand, (seeing how it doesn't open when heat is on max) and loosen the 17mm bolt on top of the thermostat housing. (just a little) Some coolant will come out when you do this. Just crack it so you can see the air bubbles through the coolant that spills out. If no coolant comes out then you don't have enough coolant in the system, which will cause you to have no heat. Let us know how you make out with it.
10-19-11, 12:06 PM
#3
Driver School Candidate
Thread Starter
I've bleed the system as you described as well as taking overflow cap off with front end of car slightly higher than rear and reving engine in which I seen the car burp a few times. In another post, a reply was made that my blender door may be stick but I haven't got a reply on how to get to it.
10-19-11, 12:11 PM
#4
Driver School Candidate
Thread Starter
Also, I do not get any heat. Driving or reving. it kicked in last night after getting the control valve unjammed but was very low. This morning I could not get it to. duplicate.
10-19-11, 12:27 PM
#5
Pole Position
There has got to be about 8-10 doors on the heater unit to send the air in every which way you can think of. If any one door was stuck you would still feel heat from some place; vent, defrost, rear vents, feet, etc. or a combination of them. Like I said, "very complex system". It still sounds like you have air in the system. I know it took me, and many other members, a few times bleeding it to get all the air out. One tiny air bubble and ya don't get heat. I hope it's not your heater core. Do you smell anti-freeze in the car? Is there any fog like smoke coming out of the vents and defrost? Do your windows fog up after driving the car for a while? I ask b/c those are the symptoms I had when my heater core was leaking.
10-19-11, 02:24 PM
#6
Driver School Candidate
Thread Starter
No to all of those symptoms and thanks for answering my next question. We are starting are Wisconsin winter weather so I have to resolve this asap! I'm just not ready to give the shops my well earned money for fixing this issue. I will attempt my 3Rd bleeding session in a few hrs and post back. On the blender door issue, if that door wasn't working correctly, would I still hear the shifting noise when going from hot to cold and vice versus? I'll check back in later and I really appreciate you giving me what you have to offer!
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10-19-11, 03:18 PM
#8
Pole Position
10-20-11, 05:06 PM
#10
Driver School Candidate
Thread Starter
Bleeding it again and making sure coolant was full did not help. I once again felt a little heat and took it for a spin and just went back to cold but not a/c cold. Looks like the repair shop may win this one.
10-20-11, 05:13 PM
#11
Pole Position
You might have a real tiny unnoticable leak somewhere that's letting air in. Have it pressure tested. That's what my problem was, the heater core was leaking and I didn't know until I finaly decided to take it out. Is the seal good on your cap? That could give you not enough pressure.
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