BMW M5 Fuel starvation

[AshleyHall]

My M5 wouldn't start this morning after checking to see if there was a spark I discovered no fuel was getting through. After then putting a little fuel in a cylinder, it ignited that cyliner. So I then removed the fuel line prior to the filter and got only a tiny trickle of fuel. I then trun on the ignition expecting the pump to force fuel through, and NOTHING. Next I checked the pump to see if it primed the system, after removing the rear seat and listening to the pump I only heard a few small ticks before it stopped.

So I am assuming that fuel pump needs replacing. The only thing that confuses me is why doesn't the fuel pour out of the pipe prior to the fuel filter. DOES ANYONE KNOW if there a safety restriction stopping the fuel pouring out or me blowing back into the tank or is their a blockage???

Help greatly appreciated......

[KevinM]

I'm afraid I can't help you, but if anyone can it will be someone on m5board.com.

Good luck.

[WillM5AD]

My M5 wouldn't start this morning after checking to see if there was a spark I discovered no fuel was getting through. After then putting a little fuel in a cylinder, it ignited that cyliner. So I then removed the fuel line prior to the filter and got only a tiny trickle of fuel. I then trun on the ignition expecting the pump to force fuel through, and NOTHING. Next I checked the pump to see if it primed the system, after removing the rear seat and listening to the pump I only heard a few small ticks before it stopped.

So I am assuming that fuel pump needs replacing. The only thing that confuses me is why doesn't the fuel pour out of the pipe prior to the fuel filter. DOES ANYONE KNOW if there a safety restriction stopping the fuel pouring out or me blowing back into the tank or is their a blockage???

Help greatly appreciated......

Might sound daft however I had my fuel pump replaced recently and a couple of days later my car just stopped and wouldnt start, the gauge showed quarter of a tank so I thought it was a similar problem to yours, after checking for fuel pre and post filter I finally took the fuel pump out and guess what? NO FUEL the dealer had not replaced the pump sensor correctly and the gauge showed I had more fuel than I was actually holding.
Dont know if it is the same but worth checking if there is no fuel in the tank then the pump will stop pumping and making clicking noises.
WillM5AD

[Evil vanos]

Ashley, had a friend whos M5 sufferd those problems,they changed the tank filltter,as they'r a right pain in the arse to change not many get changed ,and then his car ran great agian

[WillM5AD]

Hey Evil, us lads get everywhere :)
WillM5AD

[BMW_Jim]

AshleyHall
"So I am assuming that fuel pump needs replacing. The only thing that confuses me is why doesn't the fuel pour out of the pipe prior to the fuel filter. DOES ANYONE KNOW if there a safety restriction stopping the fuel pouring out or me blowing back into the tank or is their a blockage???"


I believe that the fuel pump is in the top of the tank with its pickup in the bottom. If it is not pumping no, or very little, fuel will come out of the pipe prior to the fuel filter.

Best,

Jim
2002 BMW M5

[AshleyHall]

Just thought I should update this thread with the answer to my problem,

It did turn out it was the fuel pump. The problem did get more confusing though. I took out the fuel pump and tested it whilst out of the car. And it was working properly, I could here it whirring no problem. What stumped me was that these pumps can become weak. i.e. the motor will work once out of the car, but not pump well enough under load. So don't be fooled.

The moral of the story is don't keep running your car too low on fuel as the petrol is actually used to keep the pump cool.

[DouglasABaker]

2 years to get it fixed? Wow, you must not drive much :)

Glad you got it handled - you should join us over at www.M5Board.Com.

d-