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Hi all,

Whilst driving yesterday on the motorway the power cut out on the car (revs dropped) I lifted my foot off the throttle, put it back on again and the power came back. Didn't have no more issues all the way to work.

On the way home it did this another 3 times, all around 70/80mph (motorway speed) But the last time it did it I decided to keep my foot on the throttle to see if the power came back and it did. It came back for a few seconds then died again then came back - that was without lifting my foot off the throttle - I just huddled into the inside lane.

It is a complete power cut.

No engine management light on, and apart from that it drives absolutely fine through the gears, I have only had it on the motorway after a long ish run.

Anyone have any ideas what could be causing this?

Car is 2001 2.2 HDI. (Removed DPF approx. 3 years ago)

Peter86 wrote:It is a complete power cut.

Does the dash die or does it still indicate RPM, temp etc.?

Do you have access to PP2K?

The dash doesn't die - only the rev + speed needle slowly decline as power is lost - then it kicks back in again.

Its happened both times in day so 99% sure the dash doesn't Christmas tree - no warning lights/errors.

Think I can get access to PP2K........

So, probably not electrical. Although I'd have thought you'd get warnings if it was a drop off in fuel pressure.

I'm hoping PP will be able to tell you something (although I'll not be holding my breath...)

A few people have mentioned EGR? Would that cause these symptoms?

It sounds like air in the fuel, could be intermittent failure of the in tank pump. When was the fuel filter last changed?

Peter

I am going to plump for 'fuel pressure regulator' as the culprit - although maybe a new fuel filter will help.

The regulator is on the back of the HP fuel pump, held on by 2 torx bolts. It has 2 small O rings inside which perish, these can be bought separately.

Its a fragile piece of kit, so if you decide to remove and clean it - be gentle.

Does your car have cruise control / does it still happen with cruise engaged?

(I'm wondering if it could be a dodgy TPS, the behaviour would make sense if the ecu 'thinks' you've lifted off).

What Ginger says is a possibility. This regulator has a filter on the end, looks like a stainless steel tube. I have never had much success cleaning them as the holes are so tiny but some don't have the filter so I took the filter off mine and have had no problems since.

Peter

Thanks for the replies guys - much appreciated.

Have any of you got any pics where the regulator is/what it looks like? I will check the O-rings tonight.

If this does look like the cause....How much are the regulators to replace? or shall I just remove the filter if it looks blocked and put it back on? (Like PeterN)

My car does have cruise control - haven't tried it with the cruise engaged - but it does do it when the cruise control button is on or off. Will try on cruise.

Pretty sure the fuel filter was changed on last service, I can always change it again.

Nobody think this is RGR related?

Tried connecting a snap on diagnostic up tonight, didn't have power to my obd port. Anybody know what fuse it could be, or anything else?

Peter86 wrote:Tried connecting a snap on diagnostic up tonight, didn't have power to my obd port. Anybody know what fuse it could be, or anything else?

Anyone ?

Sorry Peter. Umm, semi-skimmed... looks like F14 & F32 engine fuse panel.

On my old 52-plate it was F4, mjb's V-reg coupe was F10 IIRC
I'd just check all the 10A fuses