Timing Belt Noise



I own a 1998 Honda Civic EX automatic, and I’ve had the timing belt changed twice, at 75K and 165K. After the more recent replacement, my car makes a whirring noise whenever I accelerate. The noise is louder in 1st gear, and it’s obviously coming from the belt. I took it back to the mechanic and he said it was because the belt was on a little too tight. However, instead of fixing the issue, he said it’s better at this point just to let it go because the sound wasn’t very loud and as the belt wears on, it’ll slack slightly and the sound will go away.

Is he right, or is he trying to not re-do the work? I don’t want to damage my engine in any way by having a timing belt that’s on too tight. I’ve driven almost 3000 miles since the belt replacement, but the sound is still there. Thank you.


There is a tension spec for newly installed belts. “A little too tight” is not part of the spec. Timing belts don’t stretch much, and if the noise hasn’t gone away in 3K miles, it’s not going to go away. I think the noise is detrimental to whatever component is making the noise (water pump, perhaps). There should be no noise.


It could also be the idler bearings on the timing belt tensioner. An idea is to remove the accessory belts and see if the sound is still there. If the sound is gone look at all the accessories to see if a bearing is failing. At the same time the timing belt was changed, the accessory belt had to be retensioned so the sound may be coming from there.


Too tight is NOT good for the belt. It could break prematurely or destroy a bearing prematurely.

DEMAND that they fix this.


At 165k miles they SHOULD have changed the idler/tensioner pulleys along with the belt. If they did not, they have made a serious mistake along with feeding you the line about the belt loosening up.

If this whirring noise is related to a belt tensioner it’s possible that the tensioner could be on the verge of failing and if this happens you may suffer some engine damage.

I agree with Mike; demand they fix this on their dime.
Failure to replace tensioners/idlers - their fault.
Failure to make sure the belt is adjusted properly - their fault.
It is also their obligation, and duty IMHO, when removing accessory belts (AC, Power Steering, etc.) for access to the timing belt to inspect those belts and any idler/tensioner pulleys.
If they balk, you could always politely ask them to register here and explain their reasons for any of this.


Thanks for the quick and thorough reponses, folks. When they did the timing belt and the water pump, they also changed out the “serpentine belt” – does that make any difference?


You’d probably want to confirm that it is in fact the timing belt making noise, and not the tensioner or serpentine belt. Serpentine belts can make a similar noise if not adjusted properly. At any rate, they didn’t do something right and need to remedy it. If they can’t or won’t comply with your request to correct a problem they caused, you may want to chalk this one up to experience, then find a reputable shop that someone you know has good experience with. You’ll pay them for the work, but the peace of mind will be worth it.


At that mileage any idler and tensioner pulleys should have also been changed. You have idler and tensioner pulleys on both the serpentine drive belt and the timing belt. It is their obligation to check all of this since it has to come apart anyway.

My suggestion at this point would be to remove the outer serpentine belt that powers accessories such as the alternator, Power Steering pump, AC compressor, etc., start the engine, and note if the noise has gone away. If not, it’s back into the timing cover.

Checking these things is something that a knowledgeable mechanic should do when performing this repair and if they did not do this then they should go back in and cover this for you; at least labor wise.