I’ve got a 1999 Saturn SL2 that has started making this odd chirping/squealing noise when accelerating into a left turn from a stop when the car has been started in the past few minutes. The sound is like a rotating rubber object scraping intermittently against something (best description I can come up with). If I pop it into neutral and rev the engine, the sound tracks along with the engine, so I think it isn’t the transmission. Some initial googling hints at the serpentine belt, but I’m not sure. The belt seems tight and is in good condition except for being slightly glazed along a 2mm strip on the right-hand border.
Any takers? I’ll be going into the shop in a few weeks but I’d like to be forearmed with some knowledge.
If the sound tracks the speed of the engine, and not the speed of the wheels turning, it can’t be CV joints. Because it seems to happen when turning hard, I would bet on the power steering pump having a seal that’s about to fail. It could also be the water pump. It probably makes sense to replace the serpentine belt at the same time you replace either.
I’m gonna go with a bad serp belt and the additional load from the power steering pump while turning causing the belt to slip.
While I agree with Ex_Chemist about it not being a CV joint, I disagree with the thought of a seal in the power steering pump, or a failing water pump. I have never heard either of them make a noise like that.
It could also possibly, and I do mean this is a real long shot, a bad bearing for the serpentine belt or timing belt. Usually these make a growling noise, but it is just possible that it could make a squealing noise.
My advice?
Replace the serp belt, and see if the noise is still there.
Thanks for the responses. It doesn’t really happen on a hard turn per se, just like when I’m accelerating into a left turn from a full stop. Never at a rolling turn.
Within the conditions specified in post #5 (i.e. accelerating from a stop):
Does it never do it on a right turn?
Does it do on every left turn?
Do I understand correctly that it does for a few minutes after starting, but then goes away until the next time it’s started? Does that hold for any time that the engine is started, no matter how long it’s been run or how long it’s been shut off, or only when the engine has sat long enough to get cold?
Tricky question, because as it happens, I rarely encounter any right turns when the engine is dead cold. I have not taken the trouble to do exhaustive isolating tests yet, and confirmation bias could be at work. But my sense is that it only happens for about the first few minutes after the engine is started, it hits exclusively on left turns at stop signs (particularly when I’m turning into an incline, even a slight one), ceases when I straighten out of the turn, and decreases or stops entirely after 2-3 minutes of operation.
I’ve thought of a parking place where I can catch a right turn up an incline with the engine cold, so I’ll try that today if you think it would be helpful for diagnosis.
Also… the sound mainly predominates when it’s been cold-started in the past 5 minutes. I don’t notice it as much (if at all) if it had been started in the past hour, or if I’ve been driving more than 5 minutes. Again, hard to reproduce since generally I drive 2 miles to work, sit there 8 hours, then go home (making mostly left turns each route).
Occurring with acceleration is consistent with belt.
Occurring with turns points to power steering belt (which on this engine is the only belt). However, only occurring on left turns is odd. It’s possible that’s for some reason there’s more load on the power steering when turning left than when turning right. But the fact that it does it in neutral pretty well eliminates any other turn-related cause (steering linkage, wheels, etc.), so the logical conclusion is that it must be a belt noise, aggravated by the increase in power steering load when turning (which is normal).
The root cause may be the belt itself, the belt tensioner, or a problem with one of the pulleys it runs on. Pulley problems are rare. Tensioner problems are not uncommon, though they more often result in a different type of noise. I would remove the belt and check that the tensioner pulley and its bearing are in good shape, and also check for smooth tensioner pivot arm operation with a fair amount of force in the pivot arm spring. If no problem is found with the tensioner, it’s a pretty sure bet the belt is faulty.
Just to clarify, the noise happens while traveling straight, if I am accelerating into an incline from a full stop. Also, I can’t produce the noise in park or neutral while sitting at a full stop. To reproduce it, the noise has to have already started in a turn or incline. Then I can pop it into neutral (while still rolling) and observe that the sound continues, with the frequency tracking with the engine (not the transmission).
Also, you said the car only had a power steering belt, doesn’t it have a serp belt also? Or are they the same thing in this car?
I’ll still go with belt.
If you can get the sound to start and then put it in nuetral and it continues; only means that the belt is already slipping when you do this and continues to do so after it’s in neutral.
And yes, the serp belt drives the power steering.
Let me enter a $0.02 thought,
This being a 1999 vehicle, How old is the battery?
Your alternator may be working very hard to replenish the battery causing undue load on the aging serpentine belt.
One thing to remember, aging vehicles are like us as we age. There may be many contributing factors that can be grouped together into what is sometimes called “Syndrome’s”.
We all seem to wait until the engine fails to turn over before replacing an aging battery.
Just my .02 cents
Previous owner of a 1995 SL2 and I will confirm what our resident experts said - it’s the serpentine belt and/or tensioner. Change them both and you’ll be good as new.
Just got back from having my problem repaired… and the diagnosis was…
(drum roll)
Air bubbles in the automatic transmission due to a loose bolt which allowed leakage and ingestion of air.
I’m a little incredulous at this. The first thing I checked was the transmission fluid level because because I saw a very tiny leak after they fixed the valve body a few months ago. It was normal. And how could this be transmission when the chattering sound varies with the engine in neutral?
But the results don’t lie – the sound is gone after they replaced the bolt and topped off the fluid. Also, tellingly, they did not charge me for this repair. This reinforces my suspicion that it was caused by something they did incorrectly while replacing the valve body.
Does this make sense? I’m starting to wonder if there’s more to the story that they aren’t telling me (like that this caused damage that will have to be fixed in another few months).
Well, that one had us stumped.
When the car is in neutral the flywheel still spins the torque converter. So, you will still have parts moving inside the transmission, hence the continued noise while in neutral.
It does sound fishy though, the part about left turns, and some other things…
Hope the best for you and thanks for following up on this here!
Gary T, what about a motor mount? Would the engine move differently straight/left versus right turn because of a shift in torque against the differential? I have an SL1 and my car has always acted differently on tight turns. If I’m on a smooth surface like a parking garage floor the tires drag differently and will squeal more in one direction. I’ve always wondered if there is something about the differential that causes this.
This is where I was going to go. I have had bad motor mounts develop allowing the engine to raise up a bit on acceleration causing all kinds of weird problems. The tranny thing is interesting as I have had funny problems there also on some vehicles. The sloshing of the fluid may indeed have aggravated a minor problem into noise that could be heard.
Many times, the last thing fixed is the first thing that goes wrong.
I have not taken the trouble to do exhaustive isolating tests yet, and confirmation bias could be at work. But my sense is that it only happens for about the first few minutes after the engine is started, it hits exclusively on left turns at stop signs (particularly when I’m turning into an incline, even a slight one), ceases when I straighten out of the turn, and decreases or stops entirely after 2-3 minutes of operation.