Occasional high pitch whine

[djm999]

I have searched this subject and found similar topics but not quite what I am experiencing. In second or third I get a high pitch whine when I am cruising at a constant speed between 2500 and 3000 rpm. When I hear it, I can make it go away by a little less or little more accelerator. There is no notice of the whine when I am shifting through the gears at high or low pace only when I am at constant cruising speed it second or third gear.

Any thoughts?

[Alfieboy]

I've always had the same thing. When it started happening when the wife was not in the car, I took it more seriously. Exact same, give it a little gas and it goes away.

[MJH1]

Alfie, I hear that same high pitch wine in the living room, let go of some gas and she goes away!

djm99, what year of car? Could it be the air pump you hear?

[tommy3rd]

in my other manual tranny car that experienced a high pitched whine that goes away with acceleration ended up being the throwout bearing.

[judgejon]

it sounds like the idler pulley located near the alternator. This is a common issue, and is a relatively easy fix. Any good indy can listen, verify, and then quickly change out the pulley. and... I'd change the timing belt as well, just because. the cost of the belt is cheap enough. good luck.

Edited June 23, 2011 by judgejon

[djm999]

It's a 2000 996 cab 6 speed.

The water pump went out recently and I replaced it along with the t stat and serpentine belt. I was hoping the water pump replacement might take care of it but it hasn't.

[djm999]

I am still trying to understand and find this whine so today I pulled the belt and went over all the pulleys again. They all felt smooth and free spinning with no unusual play in them. I decided to take it to the auto parts store without replacing the air filter housing and intake pipes. Of course it threw the CEL without the MAF sensor plugged in but I couldn't believe there was no whine at all. The belt only has a couple hundred miles on it and it whined when I first put it on so I can't blame that. Could taking it off and putting it back explain the absence of the whine or could it have been something about the air filter housing or intake pipes?

I am confused and delighted at the same time.

[romys996]

I too have this problem. I hace 02 c4s coupe. Mine kicks in at 3rd gear 3500 RPM. I've had 2 professional mechanics including a Porsche dealership check it but neither one could give me a definitive answer. They both assured me there's nothing mechanically wrong with my car.