Won't Start fuel pump wire problem

milldorr

New Member
Joined
Jul 12, 2006
Been having many days broke down on the side of the road with this problem.

Car will not start. I can get the car to start by putting a jumper on the fuel pump drain ( grey ) wire to the alternator. However as soon as I remove the jumper the car dies. I have tried 3 different fuel pump relays. I also had Anderson install a Race Tronics fuel pump hot wire kit. They also swapped out the ECM. The car ran till I got it home then it would not start again. Also I pulled the fuel pump out and bench test and it works fine.

Any Ideas? Towing bill is getting pretty expensive.
 
Doesn't the fuel pump relay get some sort of signal from the oil pressure sending unit?

My understanding, and please correct me if I'm wrong, as soon as the oil pressure sending unit see's oil pressure, it allows the fuel pump relay to "turn-on" to send 12v to the fuel pump?

Also, have you checked the ground that is inside of the trunk? Bad connection maybe??

Steve
 
Have you checked the wire that comes from the fuse block to the hot side of the fuel pump relay. The c100 connector that plugs into the back of the fuse box has given me problemsin the past. Wire C6 Pink/Blk
Connector Pinout Diagrams
This is right below the widshield wiper motor. The connector wasn't making up. Just cleaned up and plugged back in.
 
Glad to hear :)

Hope that solves your problem permently. I chased my tail on this one for half a day after I just installed a new fuel pump and hotwire kit. Could not for the life of me figure out why the pump wasn't running until I broke out the schematics...ahhh daahhhhh did I feel stupid.

Steve
 
Put new oil sending unit in today. She starts right up!

Thanks,:D


Aaah, not sure you found the problem. The oil sending unit is just a fail safe for the fuel pump relay. When when oil is at operating pressure it alows voltage to be sent to the pump, for situations when the relay takes a dump. This allows you to get to your destinantion wqith a bad fuel pump relay. It's there as a back up for the relay

I'll try to help, Going off memory here so bare with me.

The connector that goes into the fuel tank sending unit contains three wires. Black is ground. A tan wire with a white tracer is the power wire going directly to the fuel pump do you have power at this location? Remember unless your car is running you are only going to have power for two seconds after the key is turned to the run position. This is because the ECM only allows the pump to run for two seconds when the ignition is turned to the run position. The third wire is a power wire also; it is the one that is connected to the rheostat in your tank, it tells your gauge what fuel level to read depending on how much voltage it is receiving.


Check the fuel pump relay wires. The fuel pump relay is the middle relay on the passenger side fender. One of the wires connected to this relay is a dark green wire with a white tracer, located in pin A1 of the fuel pump relay wire harness socket assembly. When you turn the key to the run position the ECM triggers 12 volts for two seconds to the Dark green wire with a white tracer. In order to check this wire for power you will need some help. Get your test light on this lead and have your assistant turn the key to the run position, it should turn on the test light for two seconds, does it?

If the test light indicates you have power for two seconds then the internal Ecm relay is working. If it does not light then there is a problem with this circuit.

If it lights then turn the ignition key to off and probe the tan with white tracer wire plugged into the fuel pump relay (socket B).

Did it light up for two seconds?

If it did not light up check the black with white tracer, is it making a good ground?

If the ground is good and the tan with white tracer is not powering up you probably have a bad relay.



Hope this makes sense.
 
He is right.:wink:
Check the relay.
Possible the relay is not energized or the contacts are shot or a bad connction.
 
Trying to test voltage to pump prior to installing hotwire, how would I do that, I have unplugged but as mentioned above will only get power for two seconds and I can't run and dive under the car that fast. :)
Would jumping the jumper do the trick? I can't imagine I'd pop anything doing that?

Should just make the hot hot right?

Thanks,
Joel
 
you may be able to probe from back of plug while running, a buddy suggested it to me. should be the outside wires with center being sender but double check
good luck
joel
 
Top