faulty air mass meter making car go into limp mode?

[alf1956]

I have had my Merc Clk 270 cdi 2005 reg at my friends garage for various jobs to be done & the car ha started to stick in gear, ie it wont change up or down & the fastest you can go is around 35mph as its reving at 3500 which sounds horrendous! It will go into reverse as well. I am torn between it being the conductor plate or the air mass meter or the gearbox conductor plate, any views on this please?

 

[PobodY]

That sounds more like the conductor plate to me. - I've got no experience with the MAF on a diesel engine, but I would have expected that to cause the engine to stumble and miss whilst not stopping it from changing gears.

As stupid as it may sound, you do have the gearbox in <C> or <S> and not <M> don't you?

 

[Petrol Pete]

Ha! I will admit to making this ^^^ mistake in my C55, I had (cheap) sunglasses on that meant I could not see the dash display properly and had selected manual instead of 'C' and I hit the road.

Only thing is with the 'speed shift' gearbox it allows you to hit the rev limiter in any gear when manual is selected. I looked a right nkob pogoing up the road in first gear

 

[Old spanners]

There must be fault codes if it's in limp mode to give an idea of the problem.

 

[alf1956]

I think that people are right in suggesting that I have the car on star computer to diagnose the fault, I am in Sheffield does anybody know anybody who has a star computer that is in my locality ?

 

[mercman111]

my car is a 2003 w209 2.7 diesel also my symptoms were limp mode,no missfire,car would not kickdown,used icarsoft i980 came up with code 0102 replaced maf all ok now.