engine cut off whilst driving maybe fuel pump?

Please Help - Golf MATCH TDI 2003
My engine cut off whilst I was driving. After turning the key for about 30 secs I get the engine back on but loses power pretty much staright away. I had it towed to the garage and it started up first time for the mechanic and he replaced the fuel filter.
I had No problems for a month but every time I turn the key once(before i switch on the engine) i was hearing a kind of drumming noise coming from the rear of the car for about 4 seconds but the car worked perfectly fine.
Then last week it happened again - it cut off whilst my wife was driving.
Same thing but this time after turning the key and cranking the engine for a good 20 seconds the car starts but cuts out again if the engine falls below 1000 revs.
I managed to get it to the garage again and there was no problem when the mechanic tried it.
We decided to replace the relay 109 just to rule that out.

Its running fine at the moment but i'm wary that its going to happen again.
I still get a noise when i turn the ignition. I've heard this is normal as the fuel pumps priming but I only started hearing this noise after the first incident occurred?

Any ideas what could be causing this to happen?
Also both times the engine cut out I was low on fuel but not near empty (enough for another 50+ miles).

The noise is your fuel lift pump in the tank. If there is very little fuel in the tank, it makes more apparent noise. (more fuel muffles the sound.)

You may have a lift pump going bad, either way I would keep my own tank much closer to full than empty. (It costs about the same.)

Bill

engine shuts off

When was fuel filter replaced?

fuel filter was replaced after the first time it happened since then it happened(cut out) once again.
Now the noise I hear when i first turn the key (which i think is to do with the fuel pump in the tank) is intermittent.

Your fuel pump may very well be going bad. Get your car to your mechanic and have him do a fuel pressure test to determine if the fuel pump is functioning properly.

I would check for air bubbles in the fuel line. You may have a leak.

It cut out again!!!
I got it towed to the Dealer. They kept it for diagnostics.
I got a phone call saying it was most probably the tandem(mechanical) pump but he wasn't sure. I told him I thought it might be the lift pump in the tank so please do further diagnostics - got a call a day later saying he was 99% sure it was the tandem pump. He changed it and it still didnt start up(luckily).
They then just replaced the lift pump. The drumming noise has stopped and back to its normal whirring noise instead and has not cut out yet but I did notice that the revs drop rapidly when changing gears.
Getting it serviced today at local garage

I am not sure what you mean about revs dropping quickly when shifting gears. Isn't this normal and expected?

Throttle body cleaning? Make darn sure they do not spray cleaner down into your intake manifold. A tiny bit sprayed on the intake flapper may be ok, but flushing a bunch of cleaner down into your intake can be very bad. Carbon chunks can get into your valves and foul them, and if you get too much in your cylinders it can cause bent rods and lower end damage.

The proper way to clean the intake is to remove it, and clean it off the car.

Please forgive me if I am telling you obvious stuff you already know.

DanG

what i mean by revs dropping quickly is that just say the needle is pointing at 20 when i put the clutch down to change gears it shoots right down to 10. I know it is normal to drop down but today when i did the same it was normal it went from 20 - 15.

Solved

IT SEEMS THAT CHANGING THE LIFT PUMP (Electrical Pump in the tank) solved my cutting out problem.