3.0 turbo diesel suddenly rev surging?

[Grindle]

Anyone know why our 335D would suddenly surge to 5,000 rpm then settle back down again quite soon after i lifted the accelerator pedal? I had pulled away briskly but not that fast, then backed off but it revved right up to 5,000 rpm and then dropped back and seems ok so far driving gently. The car has sat 3 months undriven before we bought it this week, in case that's any clue. Disconcerting in a 30 mph limit.

[Alonso92]

Sorry cant help, but sounds like you need to give it a proper Italian tune

[Prinny]

Loose floormat?

[Grindle]

It's getting new automatic transmission fluid next week which could help and then Simon at E Maps is giving it a decent boost of power and torque. If there is something wrong like a leaking turbo pipe hopefully we will find it or it may just be that the car needs a damn good run out which we have had no opportunity to do yet. It's stood around ages then has not been above 40 mph since. We shall see. But £6100 for a 335d coupe in very nice order and low miles seemed too good to pass up.

[gweaver]

Given the low miles and surging throttle, I'd check for diesel in the engine oil.

[A4 cabrio]

I'd be getting the over revving issue sorted out before I thought about getting it mapped.

[AlwynMike]

gweaver said:

Given the low miles and surging throttle, I'd check for diesel in the engine oil.

Me too!