I need some help please.  BMW 330D E46 2000 reg, automatic. I experienced a problem when accelerating on the motorway in that the DDE light came on and engine cut out. It did start again and as long as I don't put my foot down it's ok. Took it for a diagnostic check today but read out not definitive. They tried changing the fuel pressure regulator but this did not have any effect. They said that the problem is in high pressure fuel system and all injectors leaking off excessively. However, no resolution as to what the problem may be. Any help would be greatly appreciated. Thank you.

Hi Emma...welcome to the Club

It does sound like fuel pressure but equally there are a number of other possibilities and it is worth taking the car for a road test with a scan tool connected to read out what is occurring when it happens.

Live data is by far the most accurate way to determine the cause or at least the data captured can lead to a more accurate diagnosis.

Injectors leaking back would suggest they are worn and need replacing but for the age of the car, secondhand ones may be suitable for use.

Keep us updated on how it all goes

Cheers,  Trevor

I would go further back in the fuel system one of my sons had an issue similar with his Toyota truck it turned out to be the low pressure fuel pump. enough there to run normally at low revs, but as soon as he gave it any load it cut out due to fuel starvation  No codes showed up the Toyota dealer changed the fuel regulator, pressure sensors and MAF but still it happened. 

Then one of my sons customers (a farmer) diagnosed it as he had seen it several times with his machinery, the dealer said no chance but my son brought a low pressure pump and problem fixed.

So I would check the fuel system and filters from front to back also check the turbo variable vanes are working freely

Thank you so much Dave and Trevor.  The diagnostic people did plug it in and took it out for a run and said that it was high pressure fuel system problem but did not have a fix.  One of the injectors was replaced as it had an issue but this just resolved the lumpy drive.  I am taking the car to the garage that have looked after it for the past 7 years and I have a list for him to try:

Crank case breather filter, Diesel Filter, Pressure Sensor, Rail Pressure Sensor, Charge Airline from EGR to Inter Cooler, and I have added Low Pressure Fuel Pump 

These are all suggestions from various people.  About a month ago it was recommended that I put fuel additive in the fuel tank because of the lumpy drive, and this I did and I am now thinking that this may have contributed to the current issue.

Although the car is 17 years old, the bodywork is in amazing condition and I only do about 4,000 miles per year so I want to keep the car.  It has done 89,000 miles and I am led to believe that this is not a problem for a diesel, and it is serviced regularly so I am hoping that it can be sorted!!

Thank you again for all your help and I'll keep you posted.

My son did exactly what you have done and put in an additive which Toyota said had clogged the low pressure pump and filter, there was just enough fuel getting to the high pressure pump to allow starting and normal driving below about 2k rpm as soon as he went above that fuel starvation miss fire and engine cut out. So my money is on the low pressure pump and filter.

The BMW 3.0 engine is one of the strongest out there and capable of some monumental mileages with good maintenance so I would have no worries about you enjoying your car for a long time to come. Remember what Clarkson and co did with a 140k 3.0 D stripped out the interior fitted a cage and then raced it in an endurance event at Silverstone !! 6 hours flat out and finished in the placings. 

So ENJOY

Thank you so much Dave.  I am going to ask the garage to try the low pressure pump and filters first so keeping everything crossed.  

I will let you know how it goes.

Emma

Hi Dave

Not good news I'm afraid.  So far one of the injectors, fuel filter and low pressure pump have been changed but problem not fixed.  So far a £600 bill and the garage now suggesting the main high pressure pump might be the problem, at a coat of a further £600, but no guarantees that the problem will be fixed.  So I'm not really sure where to go from here!!  Can't afford any more parts just now especially with no guarantees.

Thank you for your help anyway.

Emma

Morning Emma

Ouch !! Is your garage a BMW specialist ? Can they take a pressure reading at the rail ? At least it would take away some of the guess work.

For the actual pump I would look at www.realoem.com put in the last 7 digits of your vin and search fuel system you should get the part number plus any alternates. The good old Google and Flea bay are a source to find a good used or re manufactured pump that does save a lot then find a friendly mechanic or garage to fit it (being sexist here as you may be very competent with spanners)

Fingers crossed for you

Dave

Hi Emma

As Dave has mentioned, a lot of readings can be taken to establish if a component is working, but what's important is how to move forwards from here.

I would advise taking it to a Diagnostic specialist who can interpret the live data to determine the cause rather than replace any more parts.

Alternatively, for the age of the car and mileage, maybe you have to consider replacing it with a new model (sounds terrible I know) but the old saying 'head and heart'

Good luck with it all,   Cheers   Trevor