Whistling under gentle acceleration

Page may contain affiliate links. Please see terms for details.

Conicuzn

New Member
Joined
Mar 28, 2015
Messages
8
Car
W208 CLK320
I've just bought a 1999 w208 clk320, and ive just noticed (presumably thanks to the windows down weather) that under acceleration, the car makes a very noticeable whistling noise. It stops if I accelerate harder, and if I take my foot off, it is most noticeable when using just enough gas to maintain speed/gently accelerate.

I tried to identify the problem, but it doesn't makebthe noise in neutral, no matter how many revs/how much pedal. So am I right in assuming it would rule out the serpentine belt, timing belt/chain etc?

It sounds very much like a serpentine belt when it's goibg, but they feel/look fine and it only does it when the car is moving with a slight amount of accelerator.

Could it be the transmission? Low on fluid maybe? I did find a tranny fluid locking pin in the ashtray just after I bought it, so is there any easy way of telling how much fluid is in there, or should I just get it replaced? Any ideas joe much this costs?

Thanks
 
I've just bought a 1999 w208 clk320, and ive just noticed (presumably thanks to the windows down weather) that under acceleration, the car makes a very noticeable whistling noise. It stops if I accelerate harder, and if I take my foot off, it is most noticeable when using just enough gas to maintain speed/gently accelerate.

I tried to identify the problem, but it doesn't makebthe noise in neutral, no matter how many revs/how much pedal. So am I right in assuming it would rule out the serpentine belt, timing belt/chain etc?

It sounds very much like a serpentine belt when it's goibg, but they feel/look fine and it only does it when the car is moving with a slight amount of accelerator.

Could it be the transmission? Low on fluid maybe? I did find a tranny fluid locking pin in the ashtray just after I bought it, so is there any easy way of telling how much fluid is in there, or should I just get it replaced? Any ideas joe much this costs?

Thanks

Hi

What exactly do you mean by 'whistle' ? Do you mean a whistle with a slight sound of a light metallic tapping noise? If yes, then I can say it is a common thing on the M112 320 engine, as I also enquired about this on this forum a few months ago.

In my W208 320, that noise only comes when pressing the gas pedal (either from standstill or when driving at a constant speed).

If I leave the car in P or N (idling) and rev the car slowly up, the noise would appear at ~1200 rpm onwards - so from its P idle speed (600rpm I think) to 1100 rpm the noise would not appear.
If this is the same symptom on your 320 then I would guess its the same noise I'm getting.
 
No, it sounds like a belt noise, not metallic at all. I'm gonna take it to MB and see what they say
 
No, it sounds like a belt noise, not metallic at all. I'm gonna take it to MB and see what they say

Ok. If possible, take it to a good MB Specialist / Independent as they will be cheaper whilst having MB-standard resources.

MB Dealers like to stick in their STAR computer and do a electronic diagnosis for £50 odd then dig deep. Its your call. Keep us posted.
 

Users who are viewing this thread

Back
Top Bottom