intermittant fuel pump, think it's a bad electrical connection

Romulus

New Member
Joined
May 12, 2002
Sorry about the length in advance :) I just bought my car recently with most of the stuff already done by the previous owner (upgraded turbo, IC, injectors, chip, 340 walbro, and other bolt ons). It has been running great until a few nights ago. I went out to take it for a spin and noticed that the fuel pump wasn't humming with the key in the 'on' position. The car turned over fine but would not fire, so I pushed on the shrader valve on the fuel rail and didn't even get a drop of fuel.. I was about to pull the line off before the fuel filter to see if there was any pressure at that point in the system, but decided to crank it once more before making a huge mess on my garage floor. Sure enough, I hear the pump run and the car starts right up. I let it run a minute and shut it off for the night.

Tonight I get in and hear the pump cut on momentarily with the ignition key in the 'on' position, but stops just before I try and start the car. Yea, the motor fired right up, but promptly died bc of no fuel.

The pump doesn't sound like it is dying, it just cuts on and off so abruptly I'm convinced a bad connection is the problem. What I don't know is how to go about tracking it down.. can someone tell me the basic wiring layout of the fuel pump (is it wired directly into the fuse box, etc)? Also, the guy installed a Volt Booster for the pump.. I know it's a controversial product, but he was convinced it's necessary for large pumps. Does this change anything about how the pump is wired, or possibly my problem? FWIW, I pressed the little test button on the volt booster and the light came on, so I assume it's getting juice and passing it through to the pump.

Again, sorry for the rambling, just trying to not leave out any details.

Thanks alot :cool: Josh:)
 
Same thing just happened to me.

I have a hot wire kit running to a Walbro 340.

My stock exhaust decided to rust off and the exhaust was moving all over the place. It melted the hot wire and blew the fuse/ relay that came with the hotwire kit. I had to switch back to the original wiring to the FP and after the exhaust was fixed, I patched up the hotwire, replaced the fuse and all is well.

I had the same symptoms: No noise, car would start and die, nothing would come from the schrader valve.

Do you know if you have a hotwire kit running to the FP?
 
If it is hotwired, pull all the wires out of the connectors and solder them. Haven't had a problem with mine since doing that. I had 3 connections that sucked and the hotwire itself was actually getting hot from drawing too many amps due to the bad connections. 100% reliable now!!!
 
Josh, I had the same problem recently.
There is a big wide connector in the trunk on the left side near the taillight. The fuel pump feed wire is in that connector, I think it's brown and sits off to one side of the connector.
My terminal backed out of the connector just enough to make intermittent contact. Give that wire a tug on both sides of the connector to make sure the terminals are still locked together.
good luck...
 
Thanks for the help guys.. I traced all the wires I could last night to look for any problems (didn't find any). I know the positive wire goes from the volt booster in the engine bay down under the car all the way to a male plug with 5 prongs on it.. this is plugged into a female box-like piece screwed to the bottom of the trunk behind the bumper. Wires comming out of it go to the fuel pump and what I'm assuming are the tail lights. I figured one of the connections in the big plug could have gotten fouled, but it looked alright. Is this the hotwire kit that everyone talks about? If so, where exactly do I solder the fuel pump wire to the main power wire without bypassing the large 5-prong connector (so I don't take power away from the lights)?

After I snooped around the car for an hour, looking thoughtfully at each connection as if it would do anything;), I tried to start the car and it fired right up.. go figure.

If I made any sense typing that, it's a miracle;)

Thanks again for the help - Josh
 
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