Groaning E240.

[Rob Roy]

I'm not 100% sure if this is the right forum to ask this question, if it turns out it should be in another technical forum my apologies - and perhaps the moderator(s) would move it please.

I recently bought a 2005 E240 and have noticed that there is an intermittent sound like a groaning pump that runs fairly loudly for about 6 or 7 secs every so often. My thoughts are its perhaps some kind of air / vacuum pump kicking in charging up an air / vacuum reserve, but I don't know for certain.

My question is - should this be so noticable when I'm sitting in the car at traffic lights, etc, or is there perhaps a fault? Do all E240's make this noise?

Thanks for any replies, they'll be much appreciated.

 

[television]

it is to hard to work out what it can be without more info. I would start the car up and leave in Idle with everything possible turned off,to see if it still made a noise, then turn on A/C, and see what happens.

malcolm

 

[malcolm E53 AMG]

I think your right in your assumption that it is an air pump. The 211 series use an air pump to assist the braking function. Other 211 owners have mentioned this on the forum and it is quite unlike anything most people have encountered on a car until you get used to it.

J Berks will no doubt comment, he has first hand experience and has posted previously on this issue. I believe some of the pumps can be quite noisy and suffer from excessive vibration, but there is a fix for this.

 

[tom7035]

I understand there is a silencing/damping kit for this SBC pump, and which I also understand was previously being fitted under warranty as it was a known fault.
For what its worth.

 

[Rob Roy]

Thank you guys, what you say makes sense to me.

I'll contact the dealer over this week and have a chat with them to see what they can do - if anything.

I thought it was just me being just too "picky", but as mentioned by malcolm210, I've never experienced anything like this before and I've had a lot of cars over my years.

 

[jberks]

Yes, sounds like the SBS to me. I still can't decide whether to pop mine back to the dealer and have the silencer kit fitted. I guess I probably will at some point if they are willing to do it under warranty.

 

[Rob Roy]

Yes, sounds like the SBS to me.

May I ask please - "SBS" (or "SBC") what exactly is that term short for? It's just so I can dazzle Service Reception with my in-depth knowledge of their vehicle when I go in about the noise.

If truth be told, I haven't a clue regarding the techy stuff on these Merc's and its still a learning curve - like last Saturday, it told me to put a litre of oil into the engine. I eventually found the oil filler, but could I find the ****** dipstick, I had to give up as I was on my way to an appointment in Glenrothes and was running out of time.
What's that famous quote - "If all else fails read the instructions!", I've now read the instructions and am so much wiser in how to measure the oil. Of course my friend now jokes with me that the car really does have a dipstick, except this one drives the car!

Rob Roy.

 

[tom7035]

SBC - Sensotronic Braking Control (or SBS - Sensotronic Braking System).

 

[Rob Roy]

Thank you tom.

 

[jberks]

Let us know if they'll fit a damper for you under warranty. It will give me some amunition if I have a go.

 

[Rob Roy]

I'll keep you guys informed.

I'm going to try and get in tomorrow / Friday (not certain though) to see the salesman who sold me the car as there are one or two things I'm not too happy with, one being the groaning pump.

 

[Rob Roy]

Went into MB Glasgow and spoke with the salesman - he commented that the noise I'm complaining about is "normal", however he agreed to have it checked by the workshops to ensure it isn't "noisier" than it should normally be.

So I'm going back to them at the end of next week.

Thanks guys.

 

[Rob Roy]

Went to the dealer's yesterday where I bought the car and met an exceptionally helpful service manager who agreed that it was indeed the pump we have talked about and that it was extremely noisey. He explained what it was for, how it worked, which models are fitted with it, there was a "damper valve" that could be retro-fitted to try and aleviate the problem, however he couldn't guarantee that it would work, but hoped that it should.

So that's where I'm at - the part has been ordered; if its coming from down South it'll be fitted next week, if it has to come from Germany then it'll have to wait as I'm heading the Beamish next weekend for the steam rally and then spending the rest of the week in the Newcastle area checking out the local brew "Nookie B".

 

[Rob Roy]

The car went into the Mercedes dealers today for the fitting of this "damper valve" assembly and I picked the car up tonight. I'm delighted to say there is a noticable difference in the operation of the SBC pump, where it actuates less often and when it does it appears more muted than before.
The noise hasn't gone completely, but from the drive home (15 miles in town & country traffic) my first reaction is this is much better.

Hope you guys with a similar problem will be as successful as I've been.

 

[Neil Plumridge]

Did the service guy happen to mention if this is also a problem for the C240? Same engine so I am guessing it is the same issue. As you can probably guess I have a C240, hence the question.

I must say having only owned the car for a few weeks (2003 W203) I am amazed by the number of things that are considered "normal" on Mercs that you wouldn't accept on a Ford Focus......

 

[jberks]

The C class doesn't have SBC (electric brakes) as far as I know so no, it doesn't aftect he C, just the current E. MB have had a lot of trouble with SBC. Allegedly its a very clever braking system and does trick things like drying the pads, hold functions etc, but unfortunatley the electric pump can be a bit intrusive. Not too bad on the diesels but on something as smooth and quiet as the v6, a pain. I may ask them to fit a damper on mine, just for the hell of it!

 

[Rob Roy]

Just really for additional info - the Service Manager mentioned Mercedes fits the same type of braking system on one of the other model ranges as well, I know it wasn't the C Class, but for the love of me I can't remember which one it was. :roll: