squeaking while accelerating 2000 Montana

My 2000 Pontiac Montana squeaks while accelerating. There is about 55,000 miles on it. At first I thought it was a belt but it would squeak the whole time if so. It only squeaks (like a mouse), every time accelerating. Any thoughts? kathyW

I owned a 1998 Montana and put 206,000 miles on it before getting a new Montana SV6 this Fall. My '98 developed a "squeak" on acceleration that turned out to be the air conditioning pulley. I replaced the belt and compressor, but the squeak actually returned after a short while! The air conditioning worked, so I just learned to ignore it :rolleyes:
As you develop more speed while accelerating, the squeak seems to go away because it becomes higher pitched and blends into the engine noise! My guess is that you also have a pulley bearing that is causing the noise.

I owned a 1998 Montana and put 206,000 miles on it before getting a new Montana SV6 this Fall. My '98 developed a "squeak" on acceleration that turned out to be the air conditioning pulley. I replaced the belt and compressor, but the squeak actually returned after a short while! The air conditioning worked, so I just learned to ignore it :rolleyes:
As you develop more speed while accelerating, the squeak seems to go away because it becomes higher pitched and blends into the engine noise! My guess is that you also have a pulley bearing that is causing the noise.
Thank you so much for your post. Nice to hear you had your van so long. That is usually our goal but vehicles are getting harder to work on with diagnostic tests and chips etc. I thought that there was only 1 belt and that was the serpentine belt. How do you get to the ac belt? Thanks so much for your help. kathyW

Thank you so much for your post. Nice to hear you had your van so long. That is usually our goal but vehicles are getting harder to work on with diagnostic tests and chips etc. I thought that there was only 1 belt and that was the serpentine belt. How do you get to the ac belt? Thanks so much for your help. kathyW

Kathy;
You are correct in that there is just one serpentine belt that drives everything! However, the 'squeak' (more like a squeal) came from the pulley on the air compressor. My first clue that it was the ac compressor is that I noticed the squeal when the ac was engaged and it went away if I shut off the ac. I first replaced the serpentine belt (cheaper solution) but that didn't cure the noise. I then had the compressor replaced and the noise went away, but only for a short time :mad:
I learned to live with it since the ac worked perfectly! The squeal / squeak would get higher pitched as the emgine reved up until it disappeared as you reached normal driving speeds (it just blended into the regular noise).

This may have nothing to do with your problem, but my 2000 Tracker developed some squeals and squeaks from the belt area, and only at startup and low speeds. Turns out that the power steering pump was misalinged from the factory. There was a factory fix which I did myself, by just realingning the pump, and now, no more squeaks! (Dealer wanted $125 to do). Maybe you have a misalinged pulley as well, as I've learned that these serpentine belts really like to have the pulleys lined up closely. Look to see if one of the pulleys seems out of position relative to the belt.

Chatty. Maybe you have a weak serpentine belt tentioner. A worn tentioner would not exert enough pressure on the belt allowing it to slip briefly causing the squeeling noise for a moment.

POSSIBLE SOLUTION for you: I actually have two, 2003 Pontiac Montana Vans.....Easy to do a comparison of parts/positioning ect....There was squealing going on around the belt....Replaced alot of stuff from the alternator to the pulleys to the water pump ect., Some forums suggested replacing the power steering pump ect.... The squeal seemed to stop from time to time, but eventually would start again.....SOLUTION: One thing that is RARELY mentioned on these forums is to check to see if ANYTHING if rubbing or touching the belt itself, especially INTERMITTENTLY......In our case, the CRANKSHAFT POSITIONING SENSOR, which is a plastic to plastic connector, which sits on a thin piece of metal was the problem...This is on the RIGHT side of the belt near the bottom of the belt, and is less than an INCH away from the belt.... This had somehow gotten lose or bent enough, where it was touching the belt(there had been recent work done on the car).....This rubbing caused it to whine line a banchee at times, and other times not so much.....It was extremely easy to move with one finger(which also explains it's INTERMITTENT contact with the belt), but make sure everything is cooled down....There doesn't seem to be a screw or anything that keeps this metal/plastic connector to the right(and again possibly touching the belt by shifting again to the left), so we bent the metal piece to the RIGHT, farther away from the belt(again no more than an INCH away...But it's now as quiet as a mouse.....So now we know if it happens again, what to look for......Hope this solves the problem.....