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HOT AIR FROM LOWER VENTS?

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Old 07-25-2001, 01:48 AM
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HOT AIR FROM LOWER VENTS?

I have noticed that there are two vents on either side of the center console near the front. No air comes out of these when the A/C or fan is off, but when you drive down the road air starts to come out of them and increases with vehicle speed. The air itself only seems moderately warm, but its as if it pulls the radiant heat from the firewall right into your legs, and as hot air rises it eventually fills the cabin. I also notice that with the A/C on the air coming out from the same vents is cold. I should mention I have an 89 RS, but I've noticed the same ducts in an 88 Z28 as well. Does anyone have a clue as to how to solve this? One more thing, for those of you who have changed your own heater core: remember that flap or door near the heater core? It is actuated by the lower slide lever - the one that adjust from hot to cold.
Apparently GM used some sort of foam in an effort so seal the duct off from the heater core. Over time the material degrades and crumbles. I think this creates a gap that enables some of the radiant heat from the core to escape and come into the cabin. When the windows are down it creates a vacuum and pulls the air through the core even without the blower on. Does this make sense to anyone? I guess I could try to replace the foam but I'm not in a hurry to rip apart my whole dash and console again.
Old 07-25-2001, 10:37 AM
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I've noticed that too. I assumed that while the a/c is off these vents stay open to out side air to promote circulation. The air is warm b/c it is coming off the block and it is the middle of summer. I'm not sure, just a guess.

------------------
1991 Chevy Camaro RS TBI w/auto
Mods:
Edelbrock TES Headers, REALLY high flow cat, 2 1/2 in catback flowmaster, 160 stat, hypertech chip, MSD ignition (rotor, cap, superconduct. wires), Bosch quad4 plugs, open air filter, all TBI mods, no smog stuff, no EGR, lots of suspention and alignment upgrades, and a big Chevy bowtie sticker on the back.

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Old 07-25-2001, 04:59 PM
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yeah, i noticed the same thing a couple of weeks ago. i then noticed that my switch was on hot [don't use the ac]. i just flipped it to cold, and haven't had the problem since. i'm not sure if it'll work for you, but that's what stopped my leg from burning.

Pat

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'92 Firebird 305 TBI
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ASCD Ram Air Hood
14X3 K&N
'00 WS6 Exhaust
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Old 07-25-2001, 09:14 PM
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Car: 89 Camaro RS
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 2.73
I have the same problem, the difference with mine is I don't have A/C, just my t-tops.. So I can have my heat set off & the fan off, and I feel hot air too.. Though I have not looked into the problem yet.

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89 RS Camaro, LO3 305 TBI
L69 Duel Snorkel Intake
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Old 07-26-2001, 01:03 PM
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Car: 89 RS 355/ 89 IROC Convert
Engine: Hot Cam 355/TPI 305
Transmission: All 700r4's
same here with all the 3rd gens I have had.


Brian

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Old 07-26-2001, 04:19 PM
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So we all have the problem, any ideas on how to fix it?
Old 07-26-2001, 09:56 PM
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It's not a problem. The car was designed that way, and it's mentioned in your owner's manual.
Old 07-27-2001, 01:25 AM
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He's right, I just checked the manual. It states the following:

"Your Camaro has a flow through ventilation system that provides a supply of outside ram air into the car when it is moving. When the vehicle is not in motion you can get a steady flow of outside air into the car with the heater or air conditioning blower running. With the side windows closed, the flow through ventilation system provides outside air flow into the front air inlet grilles, thought he vehicle and out the rear air exhaust valves"

Go figure.

[This message has been edited by simon (edited July 27, 2001).]
Old 07-28-2001, 06:49 PM
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Here is how to fix this problem. Just wanted to say sweet board!! I am new and love it already. 5 minutes and I already have several questions answered about my 94 Sonoma.

Cool Running



To lower the temperature inside the cab on those hot days, install a couple of inexpensive gas (as in natural gas) shutoff valves on both of the heater core lines inside the engine compartment. Get two ¾-inch shutoff valves (brass and stainless steel) and two 6-inch lengths of galvanized water pipe in the correct diameter for your water hose inside diameter. (you’ll want to cut each pipe in two at the middle and file the cut edge dull). Also use four reducer fittings if your water hose inside diameter is not ¾-inch.

Thsi is why you feel the heat....The hot water is still coming into your interior. Hope this helps you!!




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Forget everything they tell you and do it your way!
Old 07-28-2001, 10:06 PM
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Car: 89 Camaro RS
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 2.73
What a "cool" idea.. is there much pressure from the water pump up those lines? could it cause any damage to the pump?
Old 08-02-2001, 01:08 PM
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SLS94, isn't this what the existing heater control valve does?
Old 08-02-2001, 01:15 PM
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double post

[This message has been edited by simon (edited August 02, 2001).]
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