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Paul TVR
01-06-2007, 01:12 PM
Been looking at a 520i for my neighbour as it won't start, I found the fuel pump fuse had blown, I replaced the fuse but still the petrol pump isn't working, I removed the pump from the tank and found the two wires going to the pump had melted together and that was probably what caused the fuse to blow. I will replace the wiring but there is no voltage at the multiplug. Is the wires shorting likely to effect the fuel relay? my neighbour has said he's fed up with it and let me have it, I don't want to spend much on it by replacing everything. with the wiring sorted out the pump works so it's not that.

CarloE34
01-06-2007, 06:36 PM
Look for the fuel relays.And chance the pump.Used one is not expensive.

Paul TVR
01-07-2007, 01:20 PM
think I'll try the relay, I don't have the owners manual, how can I tell which one it is?

CarloE34
01-07-2007, 03:23 PM
i have to check it out.What type is it?
M20 or M50

CarloE34
01-07-2007, 04:55 PM
i have to check it out.What type is it?
M20 or M50

As i find out its in ECU box.You will find 3 relays.seeing from the front of the car it is the left one.Its all the same with a 12V M20 and the 24V M50.
Hope its helping you.

Greetz Carlo

Paul TVR
01-07-2007, 05:12 PM
Cheers, it is the M50 engine, when you say ECU box is that inside the car or in the fuse box under the bonnet(hood)?

Thanks for the help :)

CarloE34
01-07-2007, 06:15 PM
Cheers, it is the M50 engine, when you say ECU box is that inside the car or in the fuse box under the bonnet(hood)?

Thanks for the help :)

ECU or DME is the computer under the bonnet.If you stand in front of the car its on the left.Fuse is the right one.You see a black box and there are 4 srews to remove.
You will find the computer of the autogearbox,if he has one :D ,from the ABS en the DME.In between them you will see 3 relays.As i know it is the left one but to be sure check them all 3.Then you for 100% that its allright :D

Let me know,otherwise i have to look what else it coult be.
anytime for help

Regards

Paul TVR
01-07-2007, 06:32 PM
Cheers I just found a PDF of the Haynes manual so have printed of the fuel section and can see now where the fuel relay is :D

I still need to repair the wiring of the plug to the fuel pump but might see if I can get a new plug put on as considering it sits in fuel don't fancy a bodge job with spade connectors.

karmann
01-07-2007, 07:01 PM
Any way i could get myt hands on that manual? :D

Paul TVR
01-07-2007, 09:07 PM
http://www.zag.si/~jank/public/bmw/haynes :D

karmann
01-08-2007, 04:38 AM
:) Thanks!!

Paul TVR
01-08-2007, 04:16 PM
all fixed, pulling the relay seemed to bring the voltage back, reused the old relay but might buy a new one just to be sure. New connectors onto the pump and jobs done :) Off to the scrap yeard for some trim parts then I'll decide if I keep or sell it on.