Squeal when idle, not when accelerating

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Jillygumbo
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Squeal when idle, not when accelerating

Post by Jillygumbo » Fri Nov 09, 2018 10:43 am

I've been searching for an answer here but can only find the opposite situation. Especially in damp autumn weather (!) there is a squeal/whine when idling or when I take my foot off the accelerator, but when I press the accelerator, the whine/squeal stops.

There is also what sounds like rustling leaves coming from under my feet, audible from outside too. It's not rustling leaves but this seems to be connected.

I am not mechanically minded, so please don't suggest I try something myself. Could this be connected to the alternator belt, or cambelt, or something else. Is it something I need to get checked out sooner rather than later (Allan service will be due in March). Year 2000 diesel.

Look forward to receiving your knowledgeable response!
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Tony x
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Re: Squeal when idle, not when accelerating

Post by Tony x » Fri Nov 09, 2018 11:26 am

Squeeling when the weather is damp is almost always due to a slipping belt (that drives the alternator for example). It won't be the cam belt and can be fixed by any mechanic. However, if it's been going on for a while you may need a new belt ( not expensive) as the noise is the belt slipping which tends to damage it.
Not sure about the rustling leaf sound.

Ps like your signature comment -
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mikeonb4c
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Re: Squeal when idle, not when accelerating

Post by mikeonb4c » Sat Nov 10, 2018 3:48 pm

Mine is doing this when cold and has been for some time. Adrian my mechanic changed (i think) thr aircon tensioner and that seemed to cure it for a while. But now its back. Its in for annual welding(!) and MOT next week plus to have a look at this problem. Will try and update you (I'm wondering if its early signs of crankshaft pulley starting to go - the two halves are bonded with rubber i think, which can let go?)
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Re: Squeal when idle, not when accelerating

Post by Doone » Sat Nov 10, 2018 5:37 pm

Lift up the passenger seat and look at the alternator belts (2 belts). A customer had a rustling noise and squeal; one of the belts had frayed.

And check the bottom pulley as suggested.
Allan's closed. We recommend PGS (Plymouth Garage Services) or Mayflower Auto Services in Plymouth.
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Re: Squeal when idle, not when accelerating

Post by Jillygumbo » Fri Nov 16, 2018 6:07 pm

Thanks both. I've just started a new job and don't have the time or energy at the moment to look at this. I've dug out the alternator belt set I bought ages ago from Ian and booked Tonto in with James (Premier) to check and sort on Monday while I'm at work.

Now that it's gone warmer, it's stopped squealing!
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Re: Squeal when idle, not when accelerating

Post by Bob » Fri Nov 16, 2018 7:20 pm

Guess Tonto doesn't like the cold. :wink:
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Re: Squeal when idle, not when accelerating

Post by Jillygumbo » Wed Nov 21, 2018 6:09 pm

All sorted now. Twas the alternator and aircon belts! No more squealing!
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Re: Squeal when idle, not when accelerating

Post by Bob » Wed Nov 21, 2018 6:48 pm

Brilliant. :)
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Re: Squeal when idle, not when accelerating

Post by mikeonb4c » Thu Nov 22, 2018 12:11 am

Jillygumbo wrote: Wed Nov 21, 2018 6:09 pm All sorted now. Twas the alternator and aircon belts! No more squealing!
Exactly the same with mine. Adrian the mechanic tweaked them and no more squeal. Tis strange though as i never had that problem with my last set of belts, which is why i didnt think it was that simple. It'll be interesting to see how long they go before they start at it again :roll:
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Re: Squeal when idle, not when accelerating

Post by Doone » Thu Nov 22, 2018 7:49 pm

We love a simple fix. 😎
Allan's closed. We recommend PGS (Plymouth Garage Services) or Mayflower Auto Services in Plymouth.
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