weird noise

[GS_Beavis]

I finally got the electrical gremlins worked out and my all stock 86 GN is running pretty decent. Had it out today playing around and it started making some sort of shrieking noise under medium to high boost. Only does it under boost and sounds like it's coming from the drivers side under the hood. I don't see anything obvious wrong. Car still runs ok but sounds like a banshee going down the road. Any ideas?.......

 

[turbot2112]

id check the ac compreesor and the crank sensor.

 

[GS_Beavis]

The A/C compressor? In neutral it revs quietly, only seems to make the noise under boost. Would the compressor be boost sensitive like that? How would the crank sensor do that? I'm not doubting, just trying to understand the problem better. I'm new to these cars and trying to figure out all their quirks. Thanks for the input.

 

[turbot2112]

no, sorry youre right. you would still hear those noises in neutral.do you still have the stock turbo?

 

[Gary Wells]

Any chance that it could be a factor of rpm and not boost. If it could be rpm, I would look at the serpentine belt tensioner bearings, alternator bearings, power steering bearings , and air conditioner compressor bearings. I have had the serpentine belt tensioner pulley bearings go out and it makes itself known at high rpm first. I have also had alternator bearings go out and only whine at high rpm first.

 

[GS_Beavis]

I was poking around just looking things over around the belt area and found my problem by accident. One of the clamps on the hose from the turbo to the I/C had come loose. Don't know how it happened but I snugged it back up and problem solved. Thanks to everyone who tried to help. I'm sure I'll have more problems later as I start making a few mods. On my test drive I hosed a late model T/A with an automatic. I wasn't expecting to win but just walked away from him. He didn't seem to see the humor in it like i did........... .