W203 C220CDI AUTO lack of power

[dchantry]

Wonder if anyone can point me in the right direction.
I have a 2002 C220CDI W203 automatic with 67K miles on the clock. It seems very sluggish in comparison to my friends same car. When I pull away from a stop, the car hardly moves until I reach about 2K revs and then it goes, although it always feels like it's struggling with power. Makes pullin out into traffic really tricky.
Also, when I try to reverse up hill it's virtually impossible which is a problem as my drive is a hill . Car does reverse on the flat.
Also, what is the correct range I should expect from a full tank of petrol driving 80% motorway miles.
Just had a service and all the filters changed.
Any ideas on what I should check?

 

[television]

Wonder if anyone can point me in the right direction.
I have a 2002 C220CDI W203 automatic with 67K miles on the clock. It seems very sluggish in comparison to my friends same car. When I pull away from a stop, the car hardly moves until I reach about 2K revs and then it goes, although it always feels like it's struggling with power. Makes pullin out into traffic really tricky.
Also, when I try to reverse up hill it's virtually impossible which is a problem as my drive is a hill . Car does reverse on the flat.
Also, what is the correct range I should expect from a full tank of petrol driving 80% motorway miles.
Just had a service and all the filters changed.
Any ideas on what I should check?

You could unplug the MAF and check how the car goes without it.

 

[Uncle Benz]

Wonder if anyone can point me in the right direction.
I have a 2002 C220CDI W203 automatic with 67K miles on the clock. It seems very sluggish in comparison to my friends same car. When I pull away from a stop, the car hardly moves until I reach about 2K revs and then it goes, although it always feels like it's struggling with power. Makes pullin out into traffic really tricky.
Also, when I try to reverse up hill it's virtually impossible which is a problem as my drive is a hill . Car does reverse on the flat.
Also, what is the correct range I should expect from a full tank of petrol driving 80% motorway miles.
Just had a service and all the filters changed.
Any ideas on what I should check?

I agree with Malcolm about the MAF. Range on a full tank of petrol?? I would guess at about half a mile at most!!!!!!!

 

[dchantry]

Thanks Guys, will try.
I believe I'm going to be around 500 miles for a tank of petrol. I would say this is about right.
Regarding the power. It's better once the car warms up. In the morning when I first turn the car on I try and reverse, the car takes an eternity to go backwards up a slight incline. Also sounds like a dog until warmer.

 

[brandwooddixon]

Does the engine rev freely in nuetral?

Any black smoke under load?

Could be a MAF.

 

[Glenn Smith]

i think it may run better on diesel?

 

[dchantry]

There is no smoke. When I start it in the morning I'm unable to reverse up a hill, although it will on a flat. Also, it sounds like a dog when first started and is OK once I've driven. It's going on a diagnostic machine Friday to see what it picks up.

 

[hmang]

i think it may run better on diesel?

Daaad....i think i've done it wrong again!!

 

[dchantry]

Just seen the petrol typo, guess I need to be clear when posting. Car is definately diesel.

 

[HJHPH]

Hi there, had a similar problem with my wife's C220 cdi Sports coupe, turned out that the pre cat had failed and the debris from this had dropped down and blocked the main cat, felt like it drove but with no turbo, car also had an unusual sound, the exhaust was escaping around the sprung exhaust connection with the pre cat. MPG was also poor. Put your hand over the end of the exhaust to see if you have a good flow of exhaust from it.
Paul.

 

[dchantry]

Thanks for all the responses, I have it booked in to check out on a machine. Took a turn for the worse today. Whenever I try to reverse straight from cold it takes an eternity and if there is the slightest incline it actually cuts out.:-x

 

[Ellsy Tanners]

This sounds to me like a possible gearbox fault rather than a engine issue, have you noticed any gearbox fluid leaks/patches. Do the revs increase without the car pulling, or does it just not rev quickly atall. A low fluid level may account for this fault in that case. Have you noticed it slipping of the gearbox atall. just an idea!

 

[dchantry]

Rev's don't increase without the car moving. When I put my foot down from cold the revs don't seem to go up. Strange that after a couple of minutes the problem isn't as bad. Lucky I'm going to have it looked at (as long as it doesn't mean big bills.
The car sounds really rough at the moment so there must be something wrong.

 

[dchantry]

gggggggggggggggggg

 

[dchantry]

Had the car on a diagnostic machine. There were no active faults showing, but 1000's of stored.
Of the ones stored he did point out a few.
P0100-064 B2/5 (Hot film MAF sensor) Plausibility 3
P1470-016 Charge Pressure control positive control variation (Charge pressure is too low)
P0190-002 (Rail Pressure sensor) The signal voltage is too high.

The guy who ran the test reset the codes and has asked me to run it for a week and then return to go through it again.
I've ordered a new MAF, but looking at some of the other forums, this could turn out to be a potential minefield.
One last thing. When I was driving up a hill last night, I experienced a sudden lack of power for about 15 seconds, where I couldn't rev above a certain point (didn't get the rev readings) and the engine seems noisier than before now. It went up another hill with no problem though after, with no noticable power loss.
Any thoughts from what I've put here would be greatly appreciated.

 

[alec2]

I have the estate version.

I get about 47 to 48 mpg on the motorway.

I think mine is running properly but it has always been a bit slow on take off.
This is due to turbo lag, which is more noticeable on the automatics. This is because the torque convertor does not let you get a lot of revs on as you start off so the turbo is not working fully and you have in effect a non turbo engine with less actual power.

As the revs pick up the turbo cuts in and power comes in with a rush.

On the manuals the driver will probably slip the clutch and get the revs up and the turbo working sooner.

When cold mine is a little sluggish on the first move off.

It also quietens down as it warms up. Also remember that on autos when the engine is cold the gearchanges are delayed to higher revs so the catalyser warms up faster.

Alec

 

[W203-C220]

Hi, all sounds very familiar to my problem too. Bought my C220 CDi from a neighbour with a leaking exhaust, the pre-cat to turbo joint leaked with a partially broken clamp holding things together. Despite this it was never actually LOUD or audible, just sooty fumes escaping uner the bonnet & into the car when cold. Stealership diagnosed pre-cat failure with blocked main cat and £1400+ to replace both & clamp etc. I got a specailist to custom-fit a Stainless pre-cat with new clamp & sealing ring for £350 ish instead. They could not find any internal damage to the pre-cat anyway. Now the car runs exactly the same as before it was fixed, drives like a non-turbo 99% of the time but can suddenly turn into a car with boost for a few minutes.
If the exhaust is blocked why do I get 45 mpg overall and up to 59 mpg on motorways? I suspect the MAF sensor but am loath to change it as it may be better to leave well alone I think? Is there any long-term damage being done to the engine does anyone know?

Kevin.
C220 CDi Saloon 2001

 

[dchantry]

This saga seems to be running on.

Ive had someone look at the car.
The MAF was swapped for a working one off another car and it made no difference.
I left the car with him for a few days and he checked the valve timing, cleaned the EGR Valve, Checked the turbo and intercooler and piping and has gone over the mecahanicals of the engine.
I had the Gearbox drained and re-filled.
I'm still getting the same problem.
Can anyone recommend a Mercedes specialist in the south west or South Wales (rather not go to the dealer for obvious reasons) that I could go to?

To summarise the problems.
No power at startup, revs drop to 500 for about 20 seconds and then go normal.
Car very flat when pulling away and actually makes me have to wait longer than normal before pulling out into traffic, so no-one hit's me.
Car seems to be better when it's moving and warmer, but it still seems a little flat.
Fuel consumption showing 32 on a run, yet I get around 450 out of a tank on runs.

 

[psmart]

P1470... I remember this fault code well! Boost Pressure Control Valve Transducer. Knock this little baby out and you run a non-turbo car and get very good mpg at the sacrifice of performance.

The Rail Pressure fault code is also interesting because it indicates that the common rail is below or above par pressure wise (or the sensor is faulty). Below par pressure and you will get less fuel injected and poor atomisation. Never made many tests on this sensor but if your not injecting the correct dosage of fuel (and assuming the feedback circuit on the turbo is adjusting the air to compensate) you will be running under performance and potentially more economical as well! Either case, the ECU will go into a limp home mode.

The BPCVT can be triggered by the pre-cat to turbo clamp breaking, engine bay sooting up and the atmospheric air filter in the BPCVT becoming clogged up. If its still clogged up, then the ECU wont be adjusting the turbo boost pressure correctly as its not compensating vacuum actuation pressure to the turbo for a given atmospheric pressure. Could also trigger the ECU to go into emergency mode, disabling the Turbo completely and hence the P1470 code.

The BPCVT in the 220 is located (looking into the engine bay front to back) on the left side near the rear of the headlight/shock absorber mount point. If has two vacuum pipes into the top and what looks like an old fashioned petrol filter dangling from the bottom. An electrical connector goes halfway up on the BPCVT body.

The thing to note though is that the whole system is a closed loop control circuit. On startup, the BPCVT is fully actuated, so as the vacuum builds up the Turbo Actuator is pulled fully down engaging the Turbo into maximum exhaust gas flow. As the boost pressure builds up it is sensed by the Boost Pressure sensor on the intercooler outlet and the current to the BPCVT is altered, thus moving the Turbo Actuator arm, thus reducing boost. You also have other sensors such as the MAF which allows the ECU to determine air mass inrush and temperature and you also have a boost pressure temperature sensor on the intercooler exit.

Cant give you specific help other than the above information. Its one of those faults where you have to study and deduce through reasoned trial and error.

Regarding economy, on my 270ML I average with my driving style (when not auto-bahning) around 30mpg. With the turbo de-activated and the car loaded to 2.5ton+ we averaged over 1000 miles ~39mpg, so disabled turbo would indicate better mpg. On the C220, thrashing it I get around 35mpg but driving it normally, 50+ - but it is a computer-controlled manual, so expect less from an auto.

 

[dchantry]

Thanks for the thorough response.
I'll print it off and give it to the mechanic to look at.
One thing to note is that when I had the card retested on the machine a week after everything was reset, none of the faults were actually coming up again (in fact no faults at all) which made the guys who tested it think that they were older stored faults from a while back.