E320CDI Stuck Valve?

[gazzab]

My car has been in limp mocde for a few days. Local garage had a look at it and they reckon that it is a stuck valve ?! I guess the ECU has told them this!? Anyone heard of this before and what it might entail to fix?!
They reckon that it is exhaust valve 1 that is stuck. Apparently they need to strip the manifold to take a look BUT I think that it if it is a valve then it must mean that there is a bigger issue and/or will at least mean head work etc..

I spoke to a merc expert though who reckons it is either a vaccum valve or MAF as a stuck valve should mean the car isnt running right ie misfiring (and it isnt doing that !).
any ideas?

 

[jberks]

If the local garage doesn't have the MB diagnostic computer then they have no way to tell - and I'm not sure the ECU would be able to spot a stuck valve. The car will run badly in limp mode, but as you say, it would be misfiring badly with 1 cylinder with no compression. If its smooth but rev limited then its not the valve and the garage are trying it on.

The most common failure on all MBs these days is the MAF as your MB expert points out. These engines have very complex electronics and are not for the uninitiated - get it to the MB specialist.

 

[gazzab]

thanks
it is off to the merc indie specialist next week.
http://www.mercedes-specialist-surrey.com
I think the local garage really do think it is a valve on the head (exhaust valve 1) - they reckon bosch confirmed this to them. But as it is running fine bar the rev limit then I can only think they are wrong and it is something else. They wouldnt listen to my suggestions re MAF and Vacuum Valve.

I really cant stomach them trying to take the manifold off just to take a look and say 'ooh it isnt the valve' OR to say it is the valve and that cost you loads to find out and now we will charge you more to either reassemble or to continue with a job on a car that we arent experts on.