C220 CDi Loss of Power, Not MAF

[Blakey]

I recently bought a 51 plate W203 and found it occasionally drops into limp home mode. Having read lots of posts on here suggesting the MAF, I bought and fitted one. This didn't cure the problem so I booked the car in at MB for a full b-service.

They diagnosed a low boost vacuum and wanted £210 just to investigate. They also tried scaremongering saying the cause could be my catalytic converter which could break up and (get this) with back pressure, fragments could pass back up the exhaust causing engine damage.

They also pointed out that there was a fault in the healdamp adjustment due to lack of vacuum. Is this the same vacuum system as used in the boost system? If so, it sounds like the fault could be caused by a leak from say a perished rubber connector or something.

Can anyone shed any light on this for me?

Also, I'm totally shocked that the full b-service that supposedly includes parts does not cover replacement of the air filter, only diagnosis. Which to me is mental! When you've got the box open, why not replace the damn thing as a matter of course? Oh yes, I know the answer, They close it all back up again so they can charge labour to the nearest whole hour to fit a new one. - Same for wiper blades and fuel filter. So I bought the parts and decided to do it myself.

I hope someone can help.

Blakey.

 

[John Kerr]

I have had a similar problem on my 220 cdi c class and like yours the headlights had a loss of vacuum would drop into limp mode and had very little boost, turns out it was the acctuater on the side of the turbo wasn't holding its vaccuum it is not a part available from MB,I managed to get a turbo from a 10K car and since putting it on I have a different car twice the power and pulls from 1K revs in 6th.A simple way to check the acctuater is to take the pipe of the transducer and suck on it you should feel a resistance and also see the lever move on the side of the turbo.
If this is your problem you may get a new actuater from Turbo Technics about £50 I think.

Best of luck John Kerr

 

[Blakey]

Thanks for your reply John.

I picked up a replacement air filter to fit myself instead of paying the stealership to fit it, and although I haven't test driven the car for any length yet, I did notice that the filter cover hadn't been refitted correctly - either at the b-service I had done yesterday or previously. The three lugs at the lower side of the cover hadn't been inserted correctly and I could actually see the orange surround of the filter under the bottom of the cover. If my thinking is correct, the vacuum downstream of the filter could never have developed correctly so I may have unwhittingly discovered the reason for the poor vacuum fault. If it was the cause, I'm astounded that the stealership didn't put it right at the service.

I've got a bit of driving to do tomorrow and will put the car through it's paces to see if it drops into limp mode.

I'll report back tomorrow.

Cheers,

Blakey.

 

[John Kerr]

The air filter has nothing to do with the vacuum, the pick up comes off the servo might be worth having a look at that small pipe.

 

[Blakey]

Thanks John, can you clarify? Do you mean the brake servo?

 

[John Kerr]

Thanks John, can you clarify? Do you mean the brake servo?

Yes ,if you take the cover off the engine fuse box you will see the small pipe at the servo,this feeds all the vacuum operated units.

 

[television]

here is part of it

http://www.detali.ru/cat/oem_mb2.as...603716.604&CT=F&cat=69J&SID=80&SGR=010&SGN=01

 

[Blakey]

Thanks John and Television for your helpful input. Having a schematic to work from makes a lot of difference. Will have a look and trace everything through tonight.

I did discuss availability of the vacuum sensors with a helpful guy at my local dealership and he said they always hold them in stock which was a sign that they were a common failure item. Some other threads I have read here suggest the sensor may be the cause if the vacuum system itself is intact.

If anyone has any data as to the connections for the sensor and it's operating range eg. pressure range, current loop or voltage output etc and what the calibration range is. - I can get hold of some precision vacuum calibration equipment and test the sensor thoroughly if I have all the data.

Blakey.

 

[Blakey]

Oh Joy!!!

I finally sorted the loss of power problem out.

John Kerr, your initial advice was spot on. I traced the vacuum line all the way to the turbo actuator to find a hole in the line to the turbo. It must have been rubbing up against something. A temporary repair with some self amalgamating tape followed by a test drive, and wow what a difference!

Also, the headlamp adjustment and cabin heating all started working again properly.

Thanks again John for your expert advice. ;-)

Blakey.

 

[ChrisBillson]

I recently bought a 51 plate W203 and found it occasionally drops into limp home mode. Having read lots of posts on here suggesting the MAF, I bought and fitted one. This didn't cure the problem so I booked the car in at MB for a full b-service.

They diagnosed a low boost vacuum and wanted £210 just to investigate. They also tried scaremongering saying the cause could be my catalytic converter which could break up and (get this) with back pressure, fragments could pass back up the exhaust causing engine damage.

They also pointed out that there was a fault in the healdamp adjustment due to lack of vacuum. Is this the same vacuum system as used in the boost system? If so, it sounds like the fault could be caused by a leak from say a perished rubber connector or something.

Can anyone shed any light on this for me?

Also, I'm totally shocked that the full b-service that supposedly includes parts does not cover replacement of the air filter, only diagnosis. Which to me is mental! When you've got the box open, why not replace the damn thing as a matter of course? Oh yes, I know the answer, They close it all back up again so they can charge labour to the nearest whole hour to fit a new one. - Same for wiper blades and fuel filter. So I bought the parts and decided to do it myself.

I hope someone can help.

Blakey.

I have an E320 CDi Estate 2002 113,000 miles with FMBSH. Exactly the same symptoms - ie limp mode. Plus car seemed slightly asthmatic and turbo whistled more than I expected even when running 'properly'
MB dealership diagnosed g/box electrohydraulic fault that was replaced @ £550 and we were sent away with 'that has completely cured the fault'.
24hrs later and same fault existed.
More diagnosis.
Report by MB: faulty EGR and loss of vacuum due to h/light adjuster vacuum hose problem. Quote to repair - £800.
Original g/box fault - "not connected" - told them to b***er off.
I had also noticed engine never getting up to temperature so took it to indie for new thermostat and indie diagnosis. Indie suggested most likely to be primary catalytic converter. H/lamp adjusters nothing to do with limp mode.
Today: Indie had car in to get cat off and have a look. Cat appeared blocked and some evidence of degradation. Had catalytic converter fitted with promise to put old one back on if it did not cure it - different car.
EGR is fine and I don't need remote h/lamp adjustment.
Moral of story: MB main dealers employ monkeys, simply plug in star machine and start bolting new bits on with no proper diagnosis. They don't deserve your money.
Thermostat is simple mechanical device - mine had failed and guess what - diagnostic machine couldn't spot it.
Cat is 'passive' item - diagnostic machine can not spot fault - just the by product of it and even then attributes it to something else.

I will get MB to service the car but will get all reported works or future faults carried out by indie.

 

[sruthan]

Loss of power uphill - W210 E220 CDI 1999

The air filter has nothing to do with the vacuum, the pick up comes off the servo might be worth having a look at that small pipe.

Thanks John Kerr! Tried (almost) everything to get my car going fast uphill again e.g. changed air and fuel filters, changed MAF sensor, used Wynns EGR cleaner and countless fuel additives. Saw your post and remembered my headlamp adjuster wasn't working (didn't realise significance). Checked the servo and saw that a small vacuum hose had came off a small spur at the servo drum connection. Re-attached it (not easy cos the hose is v short and only just reaches) and bingo - power back and headlamps also adjust.

 

[alladdin]

here is part of it

http://www.detali.ru/cat/oem_mb2.as...603716.604&CT=F&cat=69J&SID=80&SGR=010&SGN=01

anyone have a copy or working link for this ?

i lost boost yesterday lasted 5 miles untill home.(drove normaly other than no power and no lights on ) but on a restart later in day all was well - local garage could find no fault codes

 

[Normanfr]

It realy annoys me when we read these sort of problems with Mercedes main dealers they are supposed to be the experts that charge us loads of money for on the whole a very poor job.

I have a 220CDI which I love driving and would not like to drive any other car but a Merc and the amazing thing is there attitude which is we are the experts so let us rip you off and pay the bill.

I do not expect to have parts fitted to my car just to see if it corrects the fault but if it doesn't never mind we will leave it on and try something else and give you a hefty bill.

 

[hydroart]

c220 power loss

I had the same Problems about a year ago with c220 for months!!! loss of power no gear change loads of engine back pressure i took it to loads of different garages got ripped off no 1 could diagnose the fault until my neighbour put me on 2 a garage in Bootle Liverpool, great guy diagnosed and fixed it same day very cheap Dave his name is 07419379966 give him a call i only use this garage now and highly recommend anyone to try him rather than get ripped off like i have been would love to list what garages to avoid but unfortunately its against the terms good luck

 

[adil1102]

Hi Guys,

I'm having issues with my car Mercedes Benz w203 C22O CDI. It loses power as soon as the gear shifts up to 3rd,It feels like the turbo doesn't kick anymore and sometimes i have issues with the brakes as well. When I opened the bonnet there were two lose pipes. I sucessfully put black one to the vacuum. But there is the white one is still lose. Any idea where this lose pipe (see attachment) fits in? Grateful if you could provide assistance guys.

 

[John Laidlaw]

It’s a vacuum pipe for something by the look of it, so for an actuator. Difficult to see- maybe the professionals on here will offer more assistance through experience of seeing that pipe often (or have an engine in front of them to look at, looking at mone will definitely not help you )

 

[bembo449]

id take that large intake pipe off for better visibility , there will be a summat open to air and id wager that pipe will just reach said pipe , so look for something in the radius of where it reaches pal