PontiacBonnevilleClub.com

Here is a stumper for anyone!
Wifes got a 97 Pontiac Bonneville. 3.8 non supercharged engine
In the last month, we had it hydrolock because of the lower intake gasket and plenum. I have since replaced the lower intake gasket, upper plenum, tune up,and rebuilt the transmission,done the water pump, idler pulley .All in the last week.
Their is a high pitch squeel coming from the pulley area ONLY after driving it 30 min or so. Me and 3 other mechanics scratched our head trying to guess if it was the alternator, the compressor etc.
So we concluded the bearing in the alternator. I went to remove it and then thought to myself...hmmm lemmie pull the belt off and run engine without the belt so only the harmonic balancer is moviing.
So i did and voila the noise is still there. so it has to be the harmonic balancer....wouldnt you think? If thats the only pulley turning...then why not the balancer right? So I go buy a brand new one, install it and guess what....noise still there.....makes no scence. If all the pulleys (alternator, power steering,water pump, idler pulley and compressor) is not turning, how could there be a noise if the harmonic balancer is brand new???

Iam totally stumped. I havent a clue what it could be. There is no driveability issue, just an extrmely loud noise.
Your thoughts and suggestions? remember noise only comes after 30 min of driving.
thanks

Remove the oil cap and see if the noise goes away. If it does, put the missing o-ring back on the PCV valve.

sure ill give that a try for sure....may I ask what the o ring would cause to give such a high pitch squeel? and thank you by the way....hope its the fix? noise driving my nukin futs!

gonna get wife to do it, my back is out. cant even stand verticle. I got tools, a shop, and she has will to learn!
Someone suggested to me crank seal but i have no leaks and its not even sweating....
I am eager to repair this as she wants to sell it and I refuse to sell any car with any issues. I beleive in Karma, what goes around comes around. The car in my opinion will be perfect or the best it can be when I sell it.
I would or have not ever mis lead anyone to make a sale. I been burnt so many times I know how crappy it feels to buy a headache. I actually had the car sold, 3 weeks ago for full asking price of $4300, took deposit and then when I went to get it saftied, enroute to shop, trans was acting funny(hunting between drive and over drive), sent it to tranny mechanic, and he re did valve body with all new solenoids, replaced torque convertor, new clutch packs and all new seals etc). I would never sell it the way it was, so I gave the lady her deposit back and had a friend fix it. Got car back but lady found another Bonneville. So I relisted it.
i want to fix this as its the last thing on the car. someones getting a good car. I never rasied the price after doing the tranny. I also just did the lower intake gaskets, upper plenum, complete tune up, rad flush,oil change,brake service, water pump, idler pulley. Yeah I spent a few bucks, but car is so mint inside and out it was worth doing the maintenance on it.
I love the car, wife absolutley hates it. My guess is we will keep it cause i wont sellit less than $4000 and thats good money for a 97 with low kms. People see the year and get scared. I dont care though. I dont need to sell it. I just want to sell it because I got to choose what I drive, so why cant the wife? I had 4 replies in 1 week, all wanting to see the car but I wont show it until i figure out this noise. thanks for the input guys!I dont know why she hates it but she does,she wants a wagon or van or hatchback so we can put the dog in it.

Had wife check PCV and low and behold the o ring was missing from the pcv valve. Had one and she installed it and I guess with some kms we will soon find out but for now she is as quiet as a kitten sleeping!!! Woot Woot

It's funny how missing a little piece of rubber causes all that hysteria to look for something major.

The same thing happened to me awhile back and I changed the alternator, belt, and tensioner. The noise stopped and I left the mechanic only to have to noise come back 15 minutes later when the car warmed up... I had a buddy mention to look at the PCV valve and o-ring. Bam! never a squeal again.

Anyways, sucks that you had to waste time and money on a new h.balancer. I'm 90% sure that noise will not come back.

wait till I tell the mechanic who did the plenum that it now cost me a harmonic balancer!!!
I know we are human and sh*t happens...but hot *dang*, they are not cheap!
I can now sell with confidence! any noise or rattle irritates the crap outa me. gotta be done right or not at all

There is no doubt or waiting for the km's to tick off. That was your problem.

willwren wrote:There is no doubt or waiting for the km's to tick off. That was your problem.

HUH????

MorePower wrote:

willwren wrote:There is no doubt or waiting for the km's to tick off. That was your problem.

HUH????

You have fixed the problem. You don't have to worry or drive it many kilometers to confirm. That was your problem, the o-ring.

WOW! I am glad I read this thread! I would have NEVER suspected to look at the PCV valve O-ring! Great info Willwren!!

yeah big kudos.....i been wrenching on cars since I was 12. Never in my career have i ever even heard that....
great advice!

Would have never guessed..great advice.