Peugeot 306 Hdi 1999 Manual - 306 irratic rough idle and varying RPM higher up - hippogrif

This is my forst post, so if you need more info please just shout. I have a problem with my 306. When cold, it has developed a rough idle, and doesn't respond brightly to the accelerator. Idle RPM varies between 980ish to 800, and it is a rough idle, almost like it's not firing properly on one of the cylinders. When the accelerator is depressed, revs increase, but not brightly. If the accelerator is then held constant the revs eventually and suddenly increase to the "right" level and the engine runs smoothly. When the accelerator is released, it goes back to idle and runs roughly again and the whole thing can be repeated. I'm thinking this could be a vacuum problem, but not sure where, or maybe a fuel supply problem or possibly a sensor problem but don't really know, anyone got any ideas?

Edited by hippogrif on 08/02/2011 at 12:01

 

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