Advice please for whine noise on E320 CDI

[Matt's Dad]

Hi everyone, I've been searching the web all evening and still not too sure the best route to go, so any advice appreciated.

I’ve just bought a 2004 54 plate E320 CDI saloon with 175,000 miles. It has full dealer service history, but after reading a few forums, I’m not so sure that counts for anything…………

There is a whine type noise that can be heard from inside the car, the sound gets louder and the pitch increases when the rpm’s increase, whilst in Park or Neutral, and whilst accelerating.

After trying a few searches, I was hoping it was the power steering pump, and when I checked the level it was on minimum - I topped it up to the correct level, but the noise stayed the same. I then thought perhaps it could be one of the pulleys, but with the bonnet up and the engine running, there only seems to be the noise of the engine, with no whine. As soon as you sit in the drivers seat you can hear it, and if you rev it, it increases.

I’m not sure if it’s my imagination, or if I get used to it as I drive it more, but the noise seems to quiet down after a while. The gears all work fine (Auto / Tip) but I’m wondering if it could do with a transmission oil change, and filter if this car has one? It also seems to vibrate when at low revs, using the torque of the engine, instead of revving it whilst accelerating - I’ll check the engine mounts tomorrow.

Sorry for all the waffle above, just trying to describe as best as I can. Any ideas what to check to cure the problem??

Also is this the W210 model?

 

[sms78]

no its a w211 model . Could be the viscous fan stuck on if that model has one . Some body on here will put you right they very good

 

[davidjpowell]

This will be a W211.

Does the Viscous fan run at all? This can make a bit of a racket if it plays up and would fit in with the revs angle. These cars were originally intended to have a sealed gearbox, but even Mercedes seem to recommend changing the oil ever 40k or so now.

 

[renault12ts]

Turbo whine?

 

[sms78]

mother in law in back seat

 

[renault12ts]

 

[ringway]

My first shot would be the alternator or an idler pulley.

If it is the alternator it will be expensive. IIRC for an alternator on an I6 320CDI engine the cost is £1800 or you can get a repair kit for around £950.00

Best of luck.

 

[sms78]

why the ?

 

[Matt's Dad]

This will be a W211.

Does the Viscous fan run at all? This can make a bit of a racket if it plays up and would fit in with the revs angle. These cars were originally intended to have a sealed gearbox, but even Mercedes seem to recommend changing the oil ever 40k or so now.

The Viscous fan is free to move ok, and doesn't trun when the engine is running (cold) There is a gearbox recon place near to me, I'll call them tomorrow to see if they can change the oil.
Thanks for the info on it being a W211, at least now I can pretend I know what I'm talking about!:bannana:

My first shot would be the alternator of an idler pulley.

If it is the alternator it will be expensive. IIRC for an alternator on an I6 320CDI engine the cost is £1800 or you can get a repair kit for around £950.00

Best of luck.

I'll try taking the belt of tomorrow, and see if the noise goes - but it just seems strange that when you stand infront of the car with the bonnet open, the whine noise cacn't be heard?

Also, regarding the reply about turbo noise - the turbo seems fine when you put your foot down, the car drops to the right gear and pulls like a train with mainly only the roar of the engine, and it changes gear so smooth - in fact the car really impressed me, I ony bought it for the Wife as a school run car but I think we'll be driving it at weekends too!



Had the 3 kids in the back seat, they soon replaced the noise with their own type of whine, the Mother in Law hasn't been in it yet, but I'm sure there'll be a few groans when she does

 

[ringway]

If you bought the car very recently from a dealer (even non-MB) take it back to them. IIRC a garage has to offer a minimum 3, months cover?

 

[renault12ts]

why the ?

That's a Doh...for the mother in law.

 

[prm]

My first shot would be the alternator or an idler pulley.

If it is the alternator it will be expensive. IIRC for an alternator on an I6 320CDI engine the cost is £1800 or you can get a repair kit for around £950.00

Best of luck.

Your joking, how much for a V6, and why so dear

 

[corned]

Hi and welcome to the forum!

If the noise is not apparent from the front of the vehicle, then this may suggest that it emanates from the rear of the engine, or the gearbox. I would expect a whining alternator (or pulley of any sort) to be very noticeable from the front of the vehicle.

Have a search on here for "Valeo radiator". Not wishing to scare you to death, but you can use the info you will find hopefully to rule out this being a problem.

If I was a betting man, however, I would go for the gearbox filter being in desperate need of changing. With the ATF of course. But please check that you do not have a Valeo radiator fitted.

 

[kwakdonut]

If it hasn't been done, get the ATF changed pronto

 

[Matt's Dad]

Thanks for all the replies, it is appreciated as I don’t know a thing about these cars!

Well, today didn’t go as planned as I didn’t have as mush spare time as I’d hoped for - but I did remove the bottom engine covers/trays and they were full of oil, and it appeared to be ATF. It looks like it’s been leaking from the oil pan, and the oil was really black. I’m booking it in for a transmission fluid and filter change, then I’ll see how it sounds.

I didn’t pull the belt off today, as I’ve got a new one coming tomorrow, along with filters - I thought if I’m taking the belt of to check the pulleys, I may aswell fit a new belt!

I can’t send the car back (and I don‘t think I‘d want to after driving it), as it was sold as seen at an auction - kind of an impulse buy, I wanted a newer car for my Wife to take the kids to school, and wanted something that would be comfy, good in the looks department, not too expensive on fuel, and not too expensive as I know it’ll get dings in the side from idiots in car parks! The E class seemed to fit the bill, and it looked good in metallic black (I don’t know the proper name for it) with 18” AMG wheels, full grey leather - and it had the all important parking sensors!

 

[skemball]

You may have some engine or gearbox ancillary resonating and touching the bodywork which is why you can hear it inside the car but not from the outside.

 

[BlackC55]

Record it for us to hear.

Does it do it at idle and get noiser when the revs are taken up?

Does it change when your move the steering?

 

[Matt's Dad]

Record it for us to hear.

Does it do it at idle and get noiser when the revs are taken up?

Does it change when your move the steering?

I'll try, might have to get the Wife to do the technical stuff I could probably just about manage uploading a photo, but obvioulsy that wouldn't help much

Yes it is at idle, and yes it gets louder and higher pitch when you increase the revs - I can't hear it as much when the revs are about mid way to full, but I think that's because the engine noise increases.

It reminds me of the old type radios that used to get interference - when I first heard it/noticed it, I assumed the radio was on but not tuned into a station - but the radio was off!

I didn’t get to collect the new filters and belt today, but will pick them up tomorrow, then remove the old belt and start the engine to see if I can definitely eliminate the pulleys/pumps.

Despite the noise, the high miles of the car and the dirty interior - I’m quickly starting to like this car! I normally drive a Range Rover Vogue TD6, and thought that was comfy with a strong engine, but I can’t believe how good this car drives with so many miles on (I just need to sort out all the jobs, it’s an ever growing list after reading pages and pages on this site!)

 

[BlackC55]

It sounds like a noisey PS pump to me.

 

[Druk]

I had the undertrays off mine fairly recently and found a slight oil weep down the right side of the engine which I supposed was the power steering. Turned out to be the engine mounting (which is oil-filled and had collapsed).
Not that there was a noise or any other noticible side effects but it could be that you are hearing the engine more if yours has also gone. My car has done 120000+ mls.