[pghMav]

Hi everyone, I've lurked here a bit but finally posting because of an issue I've been having. This has been happening for over a month now and I haven't been able to figure it out. The car starts up normally and is usually ok for a good 15 minutes or so. Then, this piercing squealing noise begins from the engine bay. It doesn't affect how the car drives or responds until I come to a stop. Then the car begins to lurch and the idle revs become sporadic, jumping up and down I'd say about 1000 RPM.

My local mechanic (who I've known for years) and I looked at it, and we thought it was the air compressor/water pump since the noise -seemed- to come from there and since a bad compressor tend to cause squealing noises.

Got it back today and needless to say, no dice. The noise came right back after about 15 minutes of driving along with the idle revs.

Here's a video of the noise. Warning to head phone users: it is a very high pitch so adjust your volume.

The car has basically been out of action for about a month now because of this; I've used it on extremely short drives when absolutely necessary but that's it...been borrowing other vehicles in the meantime. Any ideas on what it could be are greatly appreciated. I'll answer any questions to the best of my ability

[Mark963]

Sounds similar to a bad oil filter (look it up on youtube), but that comes from the filter housing. You could try the coolant bleed procedure to exercise the water pump without running the engine to see if it's that. Have you tried a mechanic's stethoscope?

[kkasson]

I wonder if that might be a PCV issue. Does it change if you open the oil filler cap while it's running? Is there excess difficulty opening the cap while it's running?