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MB Paul
MB Paul, Mercedes Technician
Category: Mercedes
Satisfied Customers: 4317
Experience:  Mercedes Benz Qualified Diagnostic Technician
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I have a 220 elegance diesel automatic 2002 it ticks over fine

Customer Question

I have a 220 elegance diesel automatic 2002 it ticks over fine and runs fine however once you press the accelerator from tick over it starts to shake and run rough as though its hunting. Turn off and start up without pressing the accelerator and its fine.

Many thanks Lester
Submitted: 5 years ago.
Category: Mercedes
Expert:  MB Paul replied 5 years ago.

I would first of all have the vehicle checked on a diagnostic tool to see if any fault codes are stored in the engine ECU.

It could be an injector fault - the injector readings should also be inspected with a suitable diagnostic tool.

Many problems are fuel pressure related on these engines - ensure that the low pressure fuel system is free from any signs of leaks & no air is present in the clear low pressure lines when the engine is running.

We also see some accelerator pedal faults - there is a built in throttle position sensor & this can cause running faults - this will usually store a fault code relating to the pedal sensor.

As with many faults if it is an intermittent one then by switching the ignition off & on again the ECU will often reset & the car runs ok again.

Best regards, Paul