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Old 07-05-2003, 04:29 PM   #1
meathead95
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mechanics i have a ?

I have a 96 olds cutlass supreme and here lately when you are accelerating the air quits blowing and when you let off the gas it starts blowing again. any ideas?
Thanks in advance
Keith
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Old 07-05-2003, 04:48 PM   #2
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do u mean the fan in the heater slows down and speeds up. if so the alternator is on ts way out, time for a new one
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Old 07-05-2003, 05:06 PM   #3
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Sounds like your vacuum supply is dropping under acceleration. See if you have a vacuum reservoir for your heater a/c controls. split hose etc.
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Old 07-05-2003, 05:28 PM   #4
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some cars im not sure if that is one of them have like a cut off switch for when ur under wide open throttle it gives u the power by turning off the a/c compressor and as the other said check all you vaccum lines for a leak
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Old 07-05-2003, 05:54 PM   #5
Dean23
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i need to read closer i thought it said shuts off when releasing throttle... i agree with a possible vac leak or maybe a poor connection somewhere and the weight transfer of accel pulls on wires and lossens the connect then on decel and cruise it comes back together
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Old 07-05-2003, 07:56 PM   #6
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A common area: there is a vacuum resevior located either next to the brake booster or near the drivers side fender/core support area. It's very easy to pull the hose off of the vacuum canister and will cause the exact thing that your describing.

As mentioned before, check your vacuum supply, canister, one-way check valve operation and if everthing is in order you could have a problem in the control head (vacuum leak) or a vacuum pod.
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Old 07-05-2003, 08:34 PM   #7
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Piston's answer is going to be right on the money...

It's probably a vacuum problem. I bet, that it doesn't quit blowing, it just blows out the defroster instead of the vents, when it happens. Classic symptoms of a vacuum leak to the canister, or check valve failure.
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Old 07-06-2003, 08:54 AM   #8
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your right it doesnt quit blowing all together it just blows on the floor and the vents quit i will check it out tomorrow thanks fellas
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