Belt Squeal? Or from something else?

Coqui258

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2003 Black Mica Protege5
When I start my car after it's been sitting for a while (i.e. in the morning), I hear a squeal similar to the noise when a belt is loose, BUT, the noise does NOT get louder when I accelerate. The noise stays steady until the car is warmed up, then it goes away.

It seems it might be the water pump? Would it squeal if it's going?

Any ideas?
 
My belt used to squeal after a cold start. The squealing got louder when I accelerated though, that's how I knew for sure it was the belt.

I sprayed some WD-40 on it and it went away. Try it, if it doesn't go away then it's not the belt.

Matt
 
I too have the exact same problem as Coqui258....Cold start squeal until warmed up.....Car is brand new 07-Mazda3 with only 2500kms.
Dealer kept it overnight to hear the sound in the morning and they replaced the tensioner......But, the noise seems to still be there - only quieter though.

I think since the belt is still new, it needs to stretch a little? Anyways, I'll let it be for now and hope it goes away......If it still makes the noise, I'll have to return to the dealer.

Many threads on this and no specific solution. Have to wait it out to know for sure.
 
A bearing that is getting ready to fail would do the same. Have a mechanic listen with a stethoscope to find out which one..
 
Did you ever figure out what it was?

Ours has been doing that lately too - only at first start up in the morning when it is cold out. And the volume has been going way up lately. I replaced the belts thinking maybe that was it, but that did not affect it at all. I even re-tensioned the belts this morning and then started the car again and it still did it. Intermittently too - not constant - comes and goes. Then goes away once warm. I listened to it with the hood open and it seemed to be coming from the front of the engine, not the back, so I am guessing it is either the PS pump or the AC compressor. Could be the alternator, but didn't sound like it was coming from back there to me. These cars do not have belt driven water pumps, eh?

Any way to figure out which component is the culprit? I would hate to have it fail with my wife driving and then cause even more damage or strand her somewhere. But not sure what else I can do other than replace everything, which is a Pain.

Car is a 03 P5 w/ 82K miles
 
Mine squealed upon initial startup and just chirped for awhile afterwards. Come to find out, it was my harmonic balancer. It shifted ever so slightly and caused the laternator belt to rub fuuny on the pulley. Unfortuantely I had to change the balancer to fix it. I would say to definately bring it to a garage and have a mechnic break out the stethoscope. You don't want to tear a belt.
 
Mine squealed upon initial startup and just chirped for awhile afterwards. Come to find out, it was my harmonic balancer. It shifted ever so slightly and caused the laternator belt to rub fuuny on the pulley. Unfortuantely I had to change the balancer to fix it. I would say to definately bring it to a garage and have a mechnic break out the stethoscope. You don't want to tear a belt.


This is more of a scream that you can hear for blocks. There is no way anyone is going to be listening to this through a stethoscope unless they want to permantly damage their hearing!!

I need to pull off one of the belts and fire it up in the AM one morning to see if I can narrow down which accessory drive is causing the problem. There isn't much running on the drives on these engines, so it won't be that hard to narrow down. Seems likely it is the water pump or PS pump - sounds like it is coming from the PS pump area, not as likely the alternator.
 
well - it has been getting worse as I knew it would. so today I pulled the belt that runs the PS and AC and confirmed the squeal is gone w/o that belt running. The AC pulley rolls freely with no friction at all, plus it should be freewheeling with the compressor off now in the winter. So pretty much has to be the PS pump - which is where the sound seemed to be coming from when I listened to it. The pulley seems stiffer than it should be.

So I ordered up a rebuild from the dealer, plus the pulley - I don't want to take any chances so will just replace it all.

I drove the car w/o the belt hooked up and it wasn't that bad w/o the PS - I could live with it. Wife would complain, so I hooked the belt back up. Squeal came back a few times to let me know it hadn't miraculously gone away or anything.

New pump should be here early next week. R&R looks pretty straightforward.
 
hmm its been a while since i last took my p5 out in the early morning. yea it does only happen when its cold out. when i started her up, i hear a sqeaking sound then after a little while, it went away. btw my ac wasnt on. when i heard it, i was like damn thats loud haha
 
hmm its been a while since i last took my p5 out in the early morning. yea it does only happen when its cold out. when i started her up, i hear a sqeaking sound then after a little while, it went away. btw my ac wasnt on. when i heard it, i was like damn thats loud haha


Well - ours progressed from only first thing in the morning when cold to pretty much all the time at low engine speeds - especially idle. It is bad enough now that I had my wife stop driving the car and drive our Suburban until I can get it fixed. I don't want that thing seizing up and throwing the belt and possibly taking out the other belt. The PS belt I'm not worried about, but the other one runs the water pump - don't want that one off. Anyway, I have a PS pump on order from the dealer - should be here tomorrow. Hopefully I can get some time to install it on Wed.
 
i think some1 said that the belts dont interfere wit the other ones. so if one goes, it wont affect the others. dont quote me on that hehe
 
yeah in helping to diagnose without pulling the belts you can turn the A/C ON - it it goes away it's probably the A/C clutch bearings. Then can steer while idling to load up the steering pump and see if that makes it worse. Then turn on the lights on high and see if the alternator is seemingly at fault. These don't always work, but are easy to try to help pinpoint a squeal. I once had a low-frequency vibration in a 626 that I finally traced to a slightly loose power steering belt. I figured it would have been squealing, but not a peep. But you really do want to figure out if your timing belt pulley bearings are going. Last I read on here the MP5 motor in non-interference, but that would still be mighty inconvenient.
 
are you sure it just wasn't the belt being too loose? The belts seem to have a small window of adjustment, too tight and they squeel, too loose and they squeel. That would be the first thing i checked. I just play around with it til it quits. And WD-40 seems like a bad way to fix it. Just a cover up really, it will prob just come back eventually.
 
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are you sure it just wasn't the belt being too loose? The belts seem to have a small window of adjustment, too tight and they squeel, too loose and they squeel. That would be the first thing i checked. I just play around with it til it quits. And WD-40 seems like a bad way to fix it. Just a cover up really, it will prob just come back eventually.

100% sure. It was intermittent and only did it when cold and would just stop for no reason. This is not a belt squeal - much louder and more like a scream. A slipping belt just cannot make that loud of a sound. Very clearly the sound of a bearing going bad. I've heard this before on other cars. Anyway, I replaced the PS pump and the squeal is gone.
 
Oh man I am having the SAME problem. It all started after I had my underdrive pulley installed. It always squeals when started up but if I let it idle during the day it will go away after the car warms up and wont come back until the next start up. Now at night it ALWAYS squeals with the lights on and it wont go away until I have been driving for a bit or I turn the lights off again.

So I am guessing it has to do with the alternator pulley?
 
I just got through fixing my belt squeal. Needless to say, the do-it-yourselfers were the last thing on the mind of the engineers who designed this car.

It is a huge pain in the ass to get it all tightened back up and put the wheel back on, take it off the jack stands, only to have it squeek again and have to do it again. All for a freakin belt. A belt should take 5 minutes, 5 freaking minutes!
 
Here's what I have learned to do. I created a hole in the fender liner just in front of the crankshaft pulley bolt head (prior Mazdas I had had a rubber plug there?). I put the car in neutral with the e-brake on. I am able to put a socket on a long extension through my 18 inch wheel's gaps and turn the engine over. As I do this, I can use a gloved hand to derail and later replace the belt.
Belt length must match for new belts. I keep pre-tested lightly used belts in the car for road replacement. 3/8" extensions too. Just make sure you have a decently long handle for this too. You learn to do this - it is WAY faster than the other way. It just assumes that you are OK tension-wise, which in your case may not be too true.
 
ARGH!!! So turns out I was wrong - it might be the belt after-all. I replaced the PS pump with a factory rebuild. Guess what - still squeals. And only at idle or near idle. Seems like the belt is slipping. So I tried tightening it - didn't help - went looser - didn't help. The power assist is also not working so well at idle now, so I am sure hoping that is the result of the belt slipping. I used a non factory belt - Goodyear, which I normally have good luck with on other vehicles - I am hoping it is either the wrong belt or just doesn't work with these pulleys very well. I plan to replace it with a Mazda belt tomorrow. If that doesn't fix it, well - I have no clue what to do next other than give up and hand the car into the dealer to make it all better.....
(bang)
 
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