PontiacBonnevilleClub.com

Hi, I'm hoping someone can point me in the right direction here on things to check on.

My 2002 3.8L non-supercharged is making a low-pitch irratic squealing noise which sounds almost like a bearing at idle, after it runs a little while. I thought it was a water pump but the noise is coming from the other end of the engine, near the upper coolant elbow. The real odd thing is, I happened to take the oil fill neck off while it was running (it took a gasp of air when I did) and the noise stopped. When I put my hand over the fill neck, it pulled some suction and after a minute or so the noise started.

My first thought is that it could be intake coolant related, but I will say the LIM gaskets have been replaced with the aluminum ones and the Dorman upper kit was installed, about 2 years ago now. It doesn't seem to be using any coolant, and the engine oil looks ok to me.

Any ideas? Could something be causing it to pull excessive vacuum in the valve cover area? And what noise could that cause? Scratching my head here. 123,000 miles now by the way.

Appreciate it!

on your PCV valve, the o ring is missing or not attached properly, start there

gonzo4191 wrote:on your PCV valve, the o ring is missing or not attached properly, start there

I had the PCV valve out, it was loose inside the canister and wasn't bound up. O-ring seemed to be in good shape.

The symptoms are classic for a pcv problem. The valve should fit pretty tightly. Is the spring there?

Archon wrote:The symptoms are classic for a pcv problem. The valve should fit pretty tightly. Is the spring there?

Yes, the spring and o-ring are there. Would would that engine noise be though, near the upper coolant elbow? The noise is only after vacuum builds up in the valve cover. Kind of a nasty sound. I tried another new PCV valve I had for another vehicle (same physical dimensions) and it made no difference.

The whistling is caused by air being sucked in past the engine seals.

are you checking for the o ring on the valve itself, not the cover?

Is this what the two o-rings should look like?

This is not my picture. Thanks to whoever posted the picture in an auto forum.

I just got these messages tonight, wasn't on since Wednesday. Gonzo was right, o-ring was missing on the valve itself (previously I had looked for the one on the cover and it was there!). The old one must have been pitched along with the old PCV valve when I replaced it about 9 months ago.

That definitely took care of it. Thanks a million you guys are great! We are looking at going into a Buick Lucerne (3.8L Series III) and trading this in because of the mileage. I would miss the great support of this site so much!

Thanks for the picture.

[quote="imidazol97"]Is this what the two o-rings should look like?

This is not my picture. Thanks to whoever posted the picture in an auto forum.