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Discussion Starter #1
Brought another fleetwood home last night. Everything seems to work as it should except the heat. It only blows through the dash vents, and it is hardly warm at 30 degrees. It does get slightly warmer as rpm's go up.

I realize the heat should not be coming through the dash vents at all. Is this a problem with the blend door behind the glove box? Combination of that and something else? I will check the heater core hose temps later today.

Thanks.
 

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Since you just got the car, you should check it out before you ask for help. If you do not know where you are starting from, how can anyone help you?
 

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Discussion Starter #3
I don't understand Fred. I am starting with a car that has heat that is not functioning properly. Exactly what it is doing, is in the first post. More than happy to add any info that is needed, just not sure what that might be.
 

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First, the temp is not controlled by the RPMs. You need to do some more troubleshooting, because the symptom is too simplistic, and your suppositions are not consistent with the way the HVAC works.
 

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Discussion Starter #5
I know temp is not supposed to be controlled by rpms. Drove the car 50 miles home, and that sure seems to be the case though. On the highway at 70 there was "some" heat out the dash vents. At three tollbooths, the temp out the vents dropped noticably to no heat. Noticed the same thing when I got off the highway and hit a bunch of stop lights.
 

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The vent temp in my '94 Caprice also drops noticeably at stop lights. My theory is that the heater core is plugged enough that at idle it won't flow enough coolant to stay warm. Bring up the RPMs and it flows more. Since plugged heater cores are standard fair on B and D bodys, and it's been a few years since I last flushed mine, it seems reasonable. The only other thing I could think of is a worn out water pump not pumping enough water at idle, but that seems very unlikely because overheating has never been an issue.
 

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Discussion Starter #7
The vent temp in my '94 Caprice also drops noticeably at stop lights. My theory is that the heater core is plugged enough that at idle it won't flow enough coolant to stay warm. Bring up the RPMs and it flows more. Since plugged heater cores are standard fair on B and D bodys, and it's been a few years since I last flushed mine, it seems reasonable. The only other thing I could think of is a worn out water pump not pumping enough water at idle, but that seems very unlikely because overheating has never been an issue.
Just flushed mine. Didn't think it would do anything after seeing only clear water coming out each way. But it worked and now have heat. 140 degrees at the two outside vents and a bit less at the 2 center.

What is normal coolant temps according to the climate control? I got 100 celsius at the pump, and 182 F at the head after extended idle. I think its bled.

The heat still only comes out the dash vents. Is it possible someone modified something for it to do this? Watching the actuator behind ash tray, it goes all the way down when I lower temp to below 70, and then only goes half way up when I raise it again. I can force it higher and it comes out the floor.
 

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Discussion Starter #8
It looks like someone intentionally crimped the black vacuum hose that goes to the steering column. I know that is for the park brake release, but could that also have something to do with where the heat blows?
 
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