nadrealista

We just bought 2005 C320 4matic with 68K miles and have this slight knocking sound that reminds me of a pulley wobble.

It comes from the belt area where power steering pump and belt tensioner pulley are. It is more pronouonced when car is cold and in drive while stopped.

I made a video of it this morning before I took it in to MB for second time. First time they changed pulley on the AC compressor but that didn't took care of it..

Has anyone had similar problem?

I am thinking it could be belt tensioner pulley but I am not sure.

Here is the video/sound clip: http://www.vimeo.com/7662672

acr2001

Mine was making a similar noise + a "belt wobble" noise for about 1 - 2 seconds when first started. They replaced a ton of parts before finally swapping out the PS pump which seems to have fixed it.

nadrealista

anyone else?

Glyn M Ruck

Does the noise change if you move the steering?

acr2001

Mine didn't - so even if moving the wheel causes no change you cant eliminate the pump. But if it does make a change then there you go.

BigBodyBenzC240

Damn M112 engines. But yeah that noise is hard for anyone to point out right off the bat. It would be a trial and error battle just to find out the source. If under warranty take it in and let the stealership deal with it.

acr2001

I think you should be happy not to have the M271 Too many reliability issues / runs too rough.

Glyn M Ruck

Yeah - my friend in Malaysia now has 760,000 Km on an M112 engined C240 in taxi service & no major repair & our office taxi here in Cape Town - E240 has gone over the 600,000 Km mark trouble free. The M112 engine & drivetrain are bullet proof.

LILBENZ230

The M271 in the 2005 cars seems pretty reliable. I'm not having any engine issues and neither is scottisha who just posted the photo of his 2005 C230 with 199k miles. It's not V6 smooth but it's pretty good for a four-cylinder!