W163 won't rev

[Mark A]

I had to drive the wifes 02 ML-270 CDI the other day, and noticed that it couldn't pull the skin off a custard (won't rev past +/- 2500rpm).

When I challenged the wife, she said that every time it comes back from our local garage (indie) it does the same and then clears. I was suspecting an issue with the MAF. If I unplug this, will it prove if it is working properly or not ?

How much for a genuine MB replacement ?

Any other likely causes.

Cheers,
Mark

 

[Ellsy Tanners]

Either a boost problem (turbo) or a throttle problem, Are you getting full throttle at the throttle acuator next to the coolant expansion tank, as i have seen loads of broken throttle cables on the ml's.

 

[Mark A]

Many thanks. I will have a look when I get home this evening, but it does seem to respond to any throttle pedal movement quickly. It just won't go past 3,000 rpm when in P or N, and when on the road, it won't go past 2,500.

Mark

 

[Mark A]

I have tried disconnecting the MAF and this made no difference. Throttle cable looks fine.

Any other ideas ?