Fuel pump urgent!! please have a look and help if you can

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treeseries
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Tue Jan 12, 2010 7:09 pm

I have changed the fuse i have changed the relay and i have a brand new fuel pump just installed? still wont start. the fuel pump isnt kicking in when i turn it over.one of the wires has molten plastic on it howeasy is this to replace or bypass???
Last edited by treeseries on Mon Jan 18, 2010 1:02 pm, edited 2 times in total.
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treeseries
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Tue Jan 12, 2010 7:11 pm

it used to be that if i replaced the pump it would start. this is my 3rd or 4th pump this year 1st new one. when they were on their way out i could tap them to get them started is this likely to be a wirig issue???
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Ranchero
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Tue Jan 12, 2010 7:58 pm

3 or 4 this year? Bloody Hell! You're going through them.

Sorry I can't really help but if you're getting molten plastic on the wire of a brand new pump, something is very wrong.
treeseries
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Tue Jan 12, 2010 9:20 pm

the pumps wire is fine its the wire that plugs into it thats molten.
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Brianmoooore
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Wed Jan 13, 2010 11:47 am

Usual procedure! Remove the relay, link 30 and 87, and see if the pump runs.
If not check for power at the pump connector.
In your case, check for power at the plug/socket cable tied to the vent pipe tube on the RH side of the seat pan first - check with a bulb between one of the brown wires and the green/purple one.
Does the wiring look damaged here?
treeseries
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Thu Jan 14, 2010 12:54 am

The live wire that plugs into the fuel pump is damaged. i havent checked yet as to whether or not its still getting power but i will do tomorrow. i have been busy today. So just to confirm the fuel pump wiring is part of the large square block connector and loom under the rear bench (drivers side).If so what else is part of this loom and is this part of the loom the same on all models cos i'll happily replace the whole section.
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Brianmoooore
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Thu Jan 14, 2010 9:12 am

Plug/socket tied to the vent tube has wiring for the fuel pump supply, fuel level sensor, fuel level light and the rear brake pad wear sensor. On models with rear drum brakes, the plug on the sub loom has a loop of wire fitted to simulate the pad sensor.
The whole sub loom is easy enough to replace, although the bolts holding up the rear of the fuel tank need to be undone to drop the tank just enough to get the pump connectors through the gap between the tank and body.
treeseries
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Thu Jan 14, 2010 10:19 am

thank you mr.Moooore i shal have a look and attack it this weekend hopefully everything going well problem solved.
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treeseries
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Mon Jan 18, 2010 1:01 pm

hi thanks for your help so far i think i've narrowed it down to one possibilty but i wanted your opinion, when i attached a light bulb to the fuel pump posi and negi the bulb lit. when i replaced the pump this time i only bought the pump not whole assembly so the brass fitting with the plug and the posi and negi wires which enter the tank are still the same, is it possible that the plug or the two wires could be at fault??? there is no visible damage but if the pumps getting power this far...? is it worth taking the pump out still plugged in and try the light bulb on the terminals inside the tank??

I have since taken the pump out of the tank and i have tried to test if there is any power coming throung the plug...however... now everytime i turn the car over it blows my no.11 fuse? pleasehelp i need this car sorted for potential buyers.
currently without a BMW 😭
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