hi did you get to the bottom of this ,iv just brought a 2005 1.8tdci focus and does the same ,any ideas and help ,much appreciated

Help please

Engine system fault light comes on when accelerating hard and car splutters and losses power.

Its not a complete loss of power, more like random rapid blips of throttle.

Keep the revs below about 2200, accelerate slowly and at normal city driving speeds you would never know there was a fault. Car still delivers 58 MPG plus so efficiency not affected.

Turning the ignition off “resets” the light. It wont come on again until accelerating hard again.

Seems to happen more when accelerating in higher gears.

Local garage told me fault code is P0001 and they replaced the fuel volume regulator sensor unit at a cost of £260.

Fault still exists despite the fact they said car was road tested. I managed to re-create the fault with 5 mins of driving!

Question is – what could the fault be if not the fuel volume regulator and how should I deal with the garage.

All advice much appreciated.

Just a thought. Could the potentiometer in the 'fly-by-wire' accelerator pedal be faulty, so that the fault is only apparent when pushing the accelerator down hard? Would presumably be checkable using diagnositc software.

Other possibility is sticking variable vanes in the turbo. If these were to stick open, an overboost condition might be created and the engine would go into limp home mode with much loss of power... Flooring it in higher gears would tend to give rise to greater boost pressure as the engine is under greater load and so would be consistent with this fault.

Innotec sell a turbocleaning kit to clean coked-up vanes though the job is possibly best left to a garage.

My old Focus did not exhibit these symptoms so othersise I am not sure what might cause the problem. Perhaps it would be a good idea to find a local Bosch diesel specialist garage rather than chance the 'fix by random repelacement' approach of many dealers / independents?