In the last month, my 98 Camaro is making a strange noise upon startup. It's not piston slap, or ticking lifters, but it's a very high pitched whine. The alternator also seems okay, as there is no noise under heavy load/charging.

It happens both on a cold start and on starts shortly after being driven.

The whine continues for about 10 seconds and then shuts off. About 10 seconds later, it will do it again for 2-3 seconds and stop immediately. I've listened a number of times, and the noise never deviates from this pattern (so far).

Help! It's very embarrassing, and I've just started a new job, so I want to nip this in the butt before it leaves me stranded somewhere.

I know on some Fords, there was a recall for fuel injector purge noise. Do our cars have the same problem?

 

Your belts might be slipping, i'd check those first, its quite a high pitched whine like your describing.

 

Higher pitch sounds usually mean one of two things:

AIR Pump or a belt noise

If it's coming from behind/below the driver's headlight, it's the AIR pump. If it's coming from the front of the motor, try swapping the serpentine belt for a new one.

The only other thing that comes to mind is the pullies themselves. Sometimes on the older models, the bearing grease gets all burnt up inside the pullies.

 

Probably the AIR pump . They cycle on and off in the first couple-few minutes after start-up.

 

It's definitely a mechanical sound and has a definite start and end point. The belts are quiet.

We noticed last night that the noise is coming from two places as described above -- near the driver's headlight, and also near the left fuel rail.

Suppose it is the air pump...if it fails, will the car run okay and not be damaged? How much is this part, and is it hard to replace? ---I wouldn't think so, but spark plugs aren't either, except in Camaros

 

I've had this noise as well, turned out to be a serpentine pulley. The grease in the bearings cooked out after awhile i guess. We ended up pulling all of the pulleys from the motor and repacking them with grease. I think there's an article on one of the ls1 tech sites that gets into more detail as to whats involved.

 

Probably AIR pump and or check valves. Pull the fuse for the AIR system and see if the noise goes away.

And a malfunction of the AIR system won't effect how the car runs but will set an SES light on the dash.

 

is it hard to repack all pulleys with grease. i find myself having the same sqeaking noise with my car. i got a new slp underdrive pulley, not yet installed,but not sure which other pulleys i should grease up?

 

It sounds like the air pump but it should not cycle, just come on for 30 seconds or so and shut off. It takes air from the air filter hose and pushes through the two rails on either side of the motor connected to the exhaust manifold. First, you can reset the PCM and see if it fixes the cycling, second, check all the hoses and connections. Finally, it is there to add air to the cats on start up to heat them up, no issues with driving it, and since it is an emissions piece it has a longer warranty - check with your dealer.