Merc turbo diesel prob

[pheasantbreeder]

Hi

I have a c250 turbo diesel estate (1999). The turbo seems to work fine at low speeds but I've suddenly noticed that at say 70 mph, if I kick down the revs increase significantly but there is hardly any increase in the speed of the car. Does anyone have any idea why this should be so.

Thanks in advance

 

[Parrot of Doom]

See the DIY section of the forum, the thread for MAF sensor, first.

 

[C250TDSportAuto]

The C250TD doesn't have a MAF sensor, does it?

 

[240D 3.0VNTi]

Yes, it does. Its mainly for emissions (EGR) control. If the computer detects something not working right then the computer will not allow boost pressure and therefore power.

 

[c250td auto]

power loss through failed turbo pipe

I've had a similar problem to the original post - 70+mph and the power dies.
One day, under full acceleration, I noticed a hiss - this was not unusual on my car, and I'd assumed that this was simply the boost of the turbo. But this day the hiss suddenly went and the power dropped immediately. The car then slowed as if it was being starved of fuel ... or air ... discussing this with my mechanic (Penfield Motors, SE1) and it sounded like a vacuum was being created between the intake, intercooler and turbo, and he quickly found a perished pipe. This pipe looked fine cold, but was sufficiently damaged to collapse under pressure and restrict airflow to the engine, hence loss of power. I presume my pipe was specific to my car and that other cars might suffer similar problems with one of the connections between the intake and the turbo. Hope this helps other owners...

 

[merc convert]

As last post check all joints on air intake upto turbo. I had this problem last week A jubilee clip that had been overtightened in the past did not hold and the pipe blew off under hard acceleration. I have also had a joint blow on the nearside behind the bumper, look for a black plastic cover and remove then look up. This was dislodged when having the aircon condensor changed.

 

[mister_cee333]

if I kick down the revs increase significantly but there is hardly any increase in the speed of the car.

You don't say whether your car is manual or auto, although you infer auto by the phrase kick down.

If it's a manual it could be a clutch problem.