Heat from the undervent and shift area.
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My car seem to have a problem with the air vents, seem like the relay doesn't work to close the vent. Whenever i am driving on highway with window down, i can feel the heat coming from the undervent(mostly on driverside), and also from the shift area...it feels like the heat coming from the tranmission and there is nothing there to block it from entering the interior. Interestingly, this doesn't happen when i turn the AC on. I was hoping someone here can help me out with this...before i take it to the dealer for a cost fortune. Thanks everyone.
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i feel the heat coming from under the driverside too, like right where my left foot is.
it's a real warm air, annoying at times.
maybe it's cuz of the hot weather.
it's a real warm air, annoying at times.
maybe it's cuz of the hot weather.
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I suspect both of you guys have V8's, the location of the lefthand cat and down pipe is very close to your right foot making for a lot of heat transfer in that area. The Inline engines have the exhaust running down the passenger side so do not suffer from this problem (not for the driver that is), unless your car is righthand drive like mine :-(
Using the air-con with the windows closed is the only cure, the moment you open the window or roof you ruin the normal flow of the air-con and will notice heat rising from the footwell/console area and going past your face.
One of our club guys went on track day in his V8 wearing very light casual shoes, he reported the heat from the transmission tunnel near the drivers foot rest almost burnt his foot.
Using the air-con with the windows closed is the only cure, the moment you open the window or roof you ruin the normal flow of the air-con and will notice heat rising from the footwell/console area and going past your face.
One of our club guys went on track day in his V8 wearing very light casual shoes, he reported the heat from the transmission tunnel near the drivers foot rest almost burnt his foot.
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I will assume that both of you have/had the A/C setpoint to a fairly low temperature and were trying to use the flow-thru capabilities of the system. Personally I would set the control to 65F or max cool (with the A/C itself off) to be sure the hot water metering valve to the cabin heater core is at an absolute minimum.
But...
In the engine compartment at the top cener of the firewall is where this valve is located, at least for the 92 SC300. This valve is operated by the mixing vane servomotor (inside the car) with a cable. You can adjust this cable for full closure of the valve by loosening the clamp holding the sheath and adjusting it for full closure while the system is demanding max cool.
Or you can simply disconnect the "pull" cable entirely and use something to tie the valve in the fully closed position throughout the summer months.
Oh, it is quite likely that if you were getting airflow from the system at the footwell then the system "thought" it was supposed to be heating, not cooling, the car, so the hot water metering valve would be at least slightly open. Turn the setpoint down (more than 5 degrees F below the actual cabin temperature to assure full closure of the metering valve), the A/C off, and if you don't like the "natural" airflow (blower off{?}) from the dash outlets resulting (cooling mode)from this then manually re-route it to the footwell.
More...
In the process of looking up the water metering valve in my 92 LS400 shop manual I noticed that it says the only way to be certain the valve is "commanded" to it fully closed position is with the setpoint at "max cool", 65F in earlier cars.
So I guess this means the only way to prevent some minimal level of heating to the cabin is to use the max cool setpoint, or manually tie the damn thing off in the fully closed position.
But...
In the engine compartment at the top cener of the firewall is where this valve is located, at least for the 92 SC300. This valve is operated by the mixing vane servomotor (inside the car) with a cable. You can adjust this cable for full closure of the valve by loosening the clamp holding the sheath and adjusting it for full closure while the system is demanding max cool.
Or you can simply disconnect the "pull" cable entirely and use something to tie the valve in the fully closed position throughout the summer months.
Oh, it is quite likely that if you were getting airflow from the system at the footwell then the system "thought" it was supposed to be heating, not cooling, the car, so the hot water metering valve would be at least slightly open. Turn the setpoint down (more than 5 degrees F below the actual cabin temperature to assure full closure of the metering valve), the A/C off, and if you don't like the "natural" airflow (blower off{?}) from the dash outlets resulting (cooling mode)from this then manually re-route it to the footwell.
More...
In the process of looking up the water metering valve in my 92 LS400 shop manual I noticed that it says the only way to be certain the valve is "commanded" to it fully closed position is with the setpoint at "max cool", 65F in earlier cars.
So I guess this means the only way to prevent some minimal level of heating to the cabin is to use the max cool setpoint, or manually tie the damn thing off in the fully closed position.
Last edited by wwest; 06-14-02 at 10:49 AM.
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i notice this too, it seemed like heat was eminating from the general area of my gated shifter. i would always put my hand around there and try to feel for more of it but couldn't ever find where it was coming from, and would only feel a whiff of it every once in a while.
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First, turn the temperature all the way down while the A/C system is fully on/enabled, then turn it off. I don't think the hot/cold blend door mixing vane motor will move with the system off.
But even so you will still feel a great deal of radiant heat from the exhaust system.
But even so you will still feel a great deal of radiant heat from the exhaust system.
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#8
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someone correct me if Im wrong, but I think I saw in a jcwhitney catalog or something like that, sheets of this material that looks like aluminum or something.. I believe they sell them for hotrod builders or major repairs, they go under the trunk and other areas underneath of certain cars to avoid getting heat from the mufflers/cat.. I will do a search on this, if I can find any info, I would say try to put some around the area where the cats go down..
#9
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uh ha!, found a couple of websites to give you an idea of what Im talking about, check them out and see what you guys think..
http://www.coolandquiet.com/product_detail.cfm?Prod=4
http://www.carpartsplanet.com/interi...nsulation.html
http://www.coolandquiet.com/product_detail.cfm?Prod=4
http://www.carpartsplanet.com/interi...nsulation.html
Last edited by Skulinex; 10-17-02 at 03:53 PM.
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In my 95 SC4 I can feel the heat coming from the crack between the hand brake and center console. I can also feel the cup holder in the center console is really hot. I havent really noticed any heat from the vent under the dash. I always have my AC temp on max cold. I never could figure out what the haet was from. Oh ya the area near the shifter is sometimes pretty hot too especially after 20 to 30 min of driving.
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)Guys, i think the problem might be the airbag module because one time i remove the stereo after driving and noticed the heat. I can feel the heat radiated from the airbag module and when i touch it, almost got my hand burned. It was so hot, the plastic logo on the module faded color and tend to melt alittle. That is the only explaination i came come up with because the heat only happen when the car is rolling on the highway and with the window down. I suspect the air circulated inside the car, under and behind the stereo and carried out that heat. I did feel the heat came from the shifting area, the cupholder near the armrest(i can make hot coffee if i put a cold one in there for awhile
) And the whole thing is gone whenever i close the window and have the AC on or off(doesn't matter). Recently, i replaced my airbag module, but didn't have a chance to feel the heat since it's winter now( don't drive with window down), but i'll give it a try in a nice winter day.
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#14
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man was this ever resolved? i almost burned my fingers touching the metal part of the parking brake lever under its cover.
car's been a little sluggish and im wondering if i should get the tranny checked out. could a failing tranny run hotter and cause this?
car's been a little sluggish and im wondering if i should get the tranny checked out. could a failing tranny run hotter and cause this?