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Hello,

My car seems to have developed some strange hollow whistling noise from the engine. I can hear it when accelerating and when revving up in neutral you can hear it when the engine is returning to idle. Sounds a bit worrying... maybe it's some belt that's slipping perhaps? Or.... any ideas?

check your airbox is bolted down tight and there are no air hose leaks/splits.

I was going to say air leak, like a 'low pitch whistle' rather than 'turbo' whistle, you will need to have a good check around all the hoses etc as Turbolag says.

It's definitely not turbo whistle as it's there's most of the time and the pitch seems to increase with the revs. Will have a nose around the airbox... anywhere else I should look?

Cheers

Maybe check:

• 1. PAS pump (low on fluid?)
  2. Auxillary belts/tensioners (a little squirt with WD 40 on the tensioner wheels bearings, pulleys and belts can help eliminate things as the noise may stop temporarily if you get the right spot)
  3. A/C compressor (try with a/c on or off)
  4. Cambelt tensioner worn/noisey beginning to seize (difficult to check yourself)

Welton wrote:Maybe check:

1. PAS pump (low on fluid?)

Funny you should mention that as PAS fluid is all over the show in the engine bay. Will check that own...

Welton wrote:2. Auxillary belts/tensioners (a little squirt with WD 40 on the tensioner wheels bearings, pulleys and belts can help eliminate things as the noise may stop temporarily if you get the right spot)

Will try.

Welton wrote:3. A/C compressor (try with a/c on or off)

Seems to do it either way

Welton wrote:4. Cambelt tensioner worn/noisey beginning to seize (difficult to check yourself)

Ouch... not looking forward to this...!

Wish


I


Knew



How To



Multi - quote someone.


I reckon you have a leak on the rubber PAS hoses to the PAS fluid bottle.
the pump will make a right old racket when low on fluid and will get a bit hot so be careful to do it ASAP even if you just bosh in some more fluid for now. (all that stuff happened on my 605)

Hm well the sound seems to be getting louder. Can even hear it when idling, although my dad (an ex-mechanic) reckons there's nothing wrong with it. But the sound wasn't there before! It SEEMS to be coming from the back of the engine, somewhere around the manifold area and is in rythm with the revs. Will check the PAS fluid when the engine cools down a bit later tonight. The car was serviced two weeks ago with the usual oil, oil filter, fuel filter change.

Any more ideas dudes/dudettes? Just don't want the engine to blow up and I am potentially going to Falmouth on Monday.... REALLY don't wanna get stranded on the motorway!

Uhm... ok...

Hm, my boss had a listen to this and said it's either a water pump (hope not!!) or, as mentioned here, a PAS pump. The pitch SEEMS to change as you rotate the steering wheel, which is what prompted his diagnosis. He suggested a complete PAS fluid change... how would I empty the system? And do I need to bleed it once I put the new one in (how?)? Aaanddd!!! What type do I need for it?

Hope you can help!

CJ

changing pas fluid is a very messy and smelly job

you will need an assistant and about 2 litres of dextron ll atf auto gear oil/pas oil (same stuff)

take the return line from the pas pump to the reservoir and point it into a bucket, plug the pas reservoir where you took the hose off so it doesnt leak, make sure the level is ok in the bottle, get your assistant start the engine and then pour new pas fluid into the pas reservoir very quickly until the all fluid going into the bucket is clean red fluid like the fluid your pouring in
switch off engine put it all back together and recheck level

there will be no need to bleed the system as you wont be affecting the pressure side of the system

James

Thank you very much Will have to try on Monday or next weekend see if it fixes the noise.