W203 220cdi won’t rev over 3000rpm

[eliot]

Hi

My car a 2003 220cdi won’t rev over 3000rpm. Have changed the maf sensor. No change. What else could it be. Car runs fine no fault codes. Just sluggish. It will sometimes go beyond 3000.

thanks for any help.

 

[mersum1es]

really neeed to read codes, too many possibilities... usually boost pressure related (so everything between air filter to exhaust tip)

 

[LostKiwi]

Needs to go on Star or similar. Can be so many things that throwing parts at it is not a sensible option.

 

[Botus]

when we get posts like this with "no codes...." I wonder is it people with a cheap phone app and a £12 quid fake adaptor that can't really detect if the car actually starts.... or a £200 plus bit of kit cable of understanding all 60 computer modules fitted to the car?

of course there will be something wrong or it would drive normally, and the other key point is Mercedes vehicle's diagnostic capability over the ODBC socket using decent kit is absolutely huge...

maybe we should insist on having info of what diagnostic work, with what exact equipment has been used so far?

expecting others to identify fixes remotely based only on guess work for anything post 2005, without dealer level kit is a bit like checking the tyre pressure on one neighbours car and wondering if it will help identify why your other neighbours car wont start

 

[eliot]

I have a iCarsoft i980. To read codes. But have look nothing.

 

[John Laidlaw]

Do you mean when in neutral ?

 

[mersum1es]

Ifi it is in limp mode, there is always reason why, and car systems will record it. Very rarely fault codes could have been disabled (mainly when incapable mapper hides his/her poor programming). Plug it on SDS.

 

[vincentfishing]

when we get posts like this with "no codes...." I wonder is it people with a cheap phone app and a £12 quid fake adaptor that can't really detect if the car actually starts.... or a £200 plus bit of kit cable of understanding all 60 computer modules fitted to the car?

of course there will be something wrong or it would drive normally, and the other key point is Mercedes vehicle's diagnostic capability over the ODBC socket using decent kit is absolutely huge...

maybe we should insist on having info of what diagnostic work, with what exact equipment has been used so far?

expecting others to identify fixes remotely based only on guess work for anything post 2005, without dealer level kit is a bit like checking the tyre pressure on one neighbours car and wondering if it will help identify why your other neighbours car wont start

I have mb11 and had a similar fault which did not show on mb11 diagnostic, was a vacuum pipe which had detached from egr

so the above comments are (in my opinion) not really helpful to posters or potential posters looking for help and might be put off by negative comments, people come on here with a problem generally looking for help, so help them not lecture them

 

[eliot]

Thanks for reply’s.

I had fault codes
1222-000
1470-000
But said not found in the database.
Cleared the codes.
Car when ok for about 10 mins.
Worked as it should but now codes are back.

Help would be great. As going on to the motorway is not great.

thanks

 

[LostKiwi]

The first code suggests a faulty throttle pedal.
The second is usually a split boost hose.
As checking boost hoses is free (and split ones are common) that's where I'd start. Splits can be hard to see so be very meticulous in your checks.
Also check for a damaged or leaking intercooler.

 

[Botus]

I have mb11 and had a similar fault which did not show on mb11 diagnostic, was a vacuum pipe which had detached from egr

so the above comments are (in my opinion) not really helpful to posters or potential posters looking for help and might be put off by negative comments, people come on here with a problem generally looking for help, so help them not lecture them

and this is why decent diagnostic kit and an understanding of what you are looking at is vital, if its aftermarket diagnostics they have various abilities to talk to certain parts of the car and running current software is also important.

when you are without stored faults, you need to look towards "live data" which will be there on decent diagnostic tools.... and you will find readings or values that would point you toward the failure (including the one you had).

I had a similar one on my father's car.... the reading for the exhaust back pressure sensor was off the scale... with help from here and 40 quid all good. It doesn't help that manufacturers call things by odd names and this is where experience / support on forums adds the value.

 

[LostKiwi]

and this is why decent diagnostic kit and an understanding of what you are looking at is vital, if its aftermarket diagnostics they have various abilities to talk to certain parts of the car and running current software is also important.

when you are without stored faults, you need to look towards "live data" which will be there on decent diagnostic tools.... and you will find readings or values that would point you toward the failure (including the one you had).

I had a similar one on my father's car.... the reading for the exhaust back pressure sensor was off the scale... with help from here and 40 quid all good. It doesn't help that manufacturers call things by odd names and this is where experience / support on forums adds the value.

And it's also why giving full information and codes where they exist is important.

 

[eliot]

Thank you. For your help. Have got a pedal off eBay. Will try that. Will check the hoses. Is there a good way to do that. Will report back with results. These forums are amazing. But people don’t always report when fixed.

Thanks again.

 

[LostKiwi]

Thank you. For your help. Have got a pedal off eBay. Will try that. Will check the hoses. Is there a good way to do that. Will report back with results. These forums are amazing. But people don’t always report when fixed.

Thanks again.

Why did you buy a pedal?
Check hoses first! Remove them, inspect them and refit them.

 

[umblecumbuz]

As LK - Why did you buy a pedal assembly before finding out what's wrong?
Why praise this forum for its expertise, then ignore the advice given?

Especially as the advice is free and the foremost check - boost hose - also costs you nothing.

 

[eliot]

Had the pedal anyway. As the kick down is not working.

 

[mersum1es]

kick down does not work because of limp mode....

I am sorry but first post didn't mention anything about codes, te you said 'but look nothing' and THEN you give codes which were actually rcorded but your universal reader could translate to mecredes specific codes. That will make sophisticated guesses from home coach even more harder.

It in not unheard pedal will go bad (for example I had to change one in my ex W211) but boost pressure probelms are so common that with general codes that absolutely first direction to go. Plus pedal fault usually won't cause boost pressure code.

Why (me inlcuded) some people are after SDS codes is that they are only ones which can pinpoint fault at best accuracy, and even them can mislead you sometimes or cannot give staright answer which is culprit. But experience with SDS codes and understanding their connection to each others help giving guidance even remote without looking the car.

Good luck, keep us reported.

 

[Botus]

I think an element (not necessarily linked to this post), could well be most driver's lack of understanding quite how complex modern cars are. Or how much data the car can spit out of a diagnostic port and why you need it

if we step back and think...
between 45 to 75 years I recon 15% might have an understanding of how/why a suffolk punch cuts the grass
go under 35 and maybe 10% know how an engine works
get down to 25 or under these days and probably less than 5% know what a piston is
and far fewer of those would have any idea what the OBDC socket does or what software is involved

or the other way round, what? 2% between 20 and 60 almost understand what half of the sensor under the bonnet are there for.

If any of that is correct maybe we should be a bit softer with newbies?

 

[umblecumbuz]

When I was six, I thought my dad knew everything.
When I was sixteen, I thought he knew nothing.
Now I'm twentysix I'm amazed at how much he's learned in such a short time!