mercedies C240

I have got a C class mercedies with a 2.5liter deisel engine automatic. it
drives fine when crusing but it will not drive more than 50 miles/hour.
and that includes puting your foot right down to the floor.
I have change the fuel filter and
check the fuel line,
But when the vehicle is not on load the rev went up to 4000rev/min whitout
cut off.
could it be the gearbox if it is what can i do
please help

"hassan25" <hassan-muhammed@nospam.hotmail.co.uk> wrote in message
news:acba083d7a5299931832f8f6c802a531@localhost.talkaboutautos.com...[color=blue]
>I have got a C class mercedies with a 2.5liter deisel engine automatic. it
> drives fine when crusing but it will not drive more than 50 miles/hour.
> and that includes puting your foot right down to the floor.
> I have change the fuel filter and
> check the fuel line,
> But when the vehicle is not on load the rev went up to 4000rev/min whitout
> cut off.
> could it be the gearbox if it is what can i do
> please help
>[/color]

You may have better luck in a Mercedes group than in a Toyota group, but
I'll give it a shot.

When you put your foot to the floor, does the engine speed change at all?
Does engine speed change without a corresponding change in vehicle speed?
If so, then the gearbox is suspect or the linkage between the throttle and
gearbox is misadjusted.

Are you getting clouds of black smoke from the exhaust? Are you getting
clouds of white smoke from the exhaust? If the answer is yes to either of
these, injector timing is probably incorrect.

As far as an unloaded engine revving to 4,000 RPM without cutoff, I guess
the answer lies in the cutoff RPM for that particular engine.
--
Ray O
correct the return address punctuation to reply