Citroen Xsara Picasso, 2.0 HDI - 2.0 HDI engine squealing with AC on

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Sat 6 Dec 2014 21:11
Citroen Xsara Picasso, 2.0 HDI - 2.0 HDI engine squealing with AC on - albapa

Hi all,

I hope someone could advise on the following symptom: in the recent cold weather, when starting the car from cold, it runs normally. However, if I switch on the AC, there is a high pitched squealing sound, which gets louder at higher revs. Switching off the AC eliminates the noise. Also, once I have driven the car and the engine is nice and warm, and I switch on the AC, there is no squealing noise, even at higher revs.

Is it possible that the cold auxiliary drive belt is more rigid and in result slipping at the higher load, and once it warms up it goes back to normal? Or could it be a problem with the AC compressor? I somewhat doubt the latter as why wouldn't it happen when the engine is warm? I would be grateful for any advice.

Cheers
Albert

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Sat 6 Dec 2014 22:54
Citroen Xsara Picasso, 2.0 HDI - 2.0 HDI engine squealing with AC on - elekie&a/c doctor

Switching on the ac puts more load on the poly vee drive belt system.It could be that the belt is worn and not providing enough grip.Certainly worth replacing before getting involved with the other rotating pulleys/idllers.Could even be a problem with the crankshaft pulley/damper.Not an unknown fault on these.

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Sat 6 Dec 2014 22:57
Citroen Xsara Picasso, 2.0 HDI - 2.0 HDI engine squealing with AC on - Peter.N.

I would certainly say its a drive belt slipping, on initially starting the car the alternator is loading the belt up as well so if its less than healthy I would suggest you change it. Could also be that the tension is not sufficient because its stretched or the tensioner isn't working properly. If the tension is not right you will see the tensioner and belt jumping at tickover.

If you order a new belt, take the old one off and measure the length, if you order one as a standard part ther is a strong likelyhood of it being the wrong length

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Sun 7 Dec 2014 21:15
Citroen Xsara Picasso, 2.0 HDI - 2.0 HDI engine squealing with AC on - albapa

Thanks for your replies.

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