Lost boost

[DaveE320CDI]

Hi Everybody, I have been taking a look at one of my friends car its a 2000 model e220cdi that has a problem with what seems like no boost pressure! i have checked all the boost pipes and intercooler and all seems fine with them, so wondering whats going on, the engine will only rev up to 3000rpm then no power almost has though its gone into limp mode,it also had a black smoke problem and when i checked the egr valve it was nearly clogged solid with soot and oily gunge so have fitted a new valve thinking this would sort out the no power problem but no any suggestions welcome cheers Dave

 

[whitenemesis]

MAF failed?

Try unplugging and seeing how it runs

 

[television]

As Peter above,,its worth trying as it sometimes proves the point,,not always,,but it does sound MAF related

 

[DaveE320CDI]

Update on the lack of boost just diconnected the maff sensor, and no difference runs just the same as it been connected

 

[television]

Update on the lack of boost just diconnected the maff sensor, and no difference runs just the same as it been connected

Then there is a good chance that it is not working

 

[andy@pcd-ltd]

I would get it stuck on a star machine and see what is going on it should log some fault codes for it and you can also check the actual values as well.

When you say you checked the boost hoses did you actually remove them to inspect them. As i have had these before that are split and this can cause low/no boost and black somke

 

[DaveE320CDI]

Update on "no boost" well there is boost pressure its me been a bit assuming that with it not wanting to rev above 3000rpm that there was a lack of boost but re-checked all hoses and intercooler and there fine and you can actually feel the boost when the pipe is removed from the egr valve and engine revved up, so what would cause it not to rev over 3000rpm? apart from that engine sounds sweet on tickover, cheers Dave