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Old 12-08-2012, 05:21 AM
Billwill Billwill is offline
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Location: South Africa
Join Date: Oct 2009
Posts: 529
Mein Auto: BMW E30 318i 1991
Originally Posted by Stoomey006 View Post
Ok so we noticed the wires to the pump were pinched between the frame and the tank so we were thinking it was a short.. Read the wiring diagram and deteimed the wire goes to the ecu, found the wire and put a jumper on it rigt to the pump.. Sure enough pump turns on and the car starts and runs like a top.. Yay! So then went to the store to get wire etc to bypass the shorted wire and splice it in.. So I cut the wire and spliced the new one on and then onto the connector and onto the pump.. Tried it and now the pump won't turn on :-( so figured only different thing is the wire we cut.. So spliced the cut wire back into the circuit and sure enough the pump turns on w the ignition but now it just keeps running instead of just for a second before I turn it over.. So that's strange.. Now I try to start it and for some reason now there's no spark :-(. All I can think of is that by cutting the wire I messed something up... There's power to the ignition coil and we tested the resistance and its fine.. So something isn't letting the plugs fire... I could cry lol. I'm driving an f150 w a slipping clutch I NEED my car to get to work.. Thought I had it all figured out and now I'm back to the drawing board
You cannot splice in a new wire and simply cut out the existing wire!
This would work if the wire in question goes only from point A to point cut the wire at points A and B and replace it with another wire...this should work.

But if the wire going from point A to point B also has internal splices going off to maybe point C and point D then cutting this wire at points A and B leaves point C and D in mid air.

What are the colors of the wires you are dealing with? I will have a look at my circuit diagrams. In the meantime return the wiring to its original status...don't cut any wires but try adding in the extra wire from the pump to the ECU as before. This will work if you have a broken wire somewhere but not if you have a wire shorting somewhere.
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