Fuel Pump issues again.

[SMWS6TA]

Ever since my Racetronix fuel pump died and was replaced I've been plagued by an electrical gremlin that doesn't go away. It's so random that I haven't been able to track it down or get close to the area to zero in on it.


It will randomly cut out, sometimes if I hit a bump, or if the road is wavy like when you go across a bridge BUT yet if I move the wires it won't cut out but when it does cut out I wiggle the wires (see pic below) and it comes back on or if it happens while in movement I can rock the car a little and 50/50 it comes back and I don't have to stop. It's worse when I start getting under 1/2 tank.

I thought it was a loose connection or ground and have pulled the pump several times and see nothing.

The arrow is where I jiggle the wire harness going into the tank. I've chased all of the wires and can't find any shorts, cuts or broken wires. I've even used a multi-meter to check for connectivity and if volts are proper. Both answers = yes.




Is this a regulator issue?

Or should I just eat the cost of a new assembly which is an expensive guess $(340)?

Need some help in what to do next......

[douglowden116]

It looks and sounds like your problem is going through the sending unit . Is there any way to remove the yellow cap and see how the wires go through the sender .

[SMWS6TA]

There is a metal circle that holds it in place form the inside the tank. It's very difficult to remove and reinstall. The wires connect to a pin that the inside wire harness attaches too.

[SMWS6TA]

Ok after getting home last night and getting stuck on the side of the road again this morning I'm about ready to burn the bitch down.



Got it home and up on a Jack stand. Started tracing the wires all over again. It looks like it's not where I thought. The relay ground wasn't loose but if I wiggled it it would cut out. So I reposition the ground and changed the way it was zip tied and it seems to fix it for now.

[douglowden116]

I hope you got it figured out , electrical shit can drive you nuts . Especially intermittent problems that cause it to die in traffic .

[Whamhammer]

I hope you got it figured out , electrical shit can drive you nuts . Especially intermittent problems that cause it to die in traffic .

Dumb question: Could a fuel pump relay thats contacts go wonky when your hitting bumps, or just enough of a vibration cause the fuel pump to cut off?

[SMWS6TA]

Not sure about stock but I have the hot wire kit with the Racetronic pump. So with that yes, it's what was happening to me. Once I figured out it wasn't the pump or even in the tank, every time I tapped the relay or ground it would cut the pump. If anyone needs an example on why you should put on a fuel pressure gauge this is one. Trying to solve this without one would have made this infinity harder.

I think cleaning up the ground spot with a wire brush and placing the ground to it and took off the relay mount tab has made the ground better. I removed the tab because it broke while I was wiggling it. I also rerouted the wire harness and placed a few zip ties that seems to have it secured. I also made sure all connectors where firmly in place and cleaned.

[0rion]

my bet is you weren't getting a good ground there......make sure you get down to clean metal with it and put a shot of dielectric grease on there. I would say it's either that or the fact you wear your watch wrong....one of those 2.

[SMWS6TA]

That's what I ended up doing. I even cleaned up the bolt you use to secure it with.


To old to change how I wear my watch, it that way comes from 2 reasons both from the Army: 1) prevents glare giving away position, it may be small but if it catches the sun just right..... and 2) it protects it more, every time I wore it facing out it got scratched or damaged.

[Whamhammer]

That's what I ended up doing. I even cleaned up the bolt you use to secure it with.


To old to change how I wear my watch, it that way comes from 2 reasons both from the Army: 1) prevents glare giving away position, it may be small but if it catches the sun just right..... and 2) it protects it more, every time I wore it facing out it got scratched or damaged.

I was 11Bravo, so you know I wore my watch like that too I also had the wristband that covered the lens as well.

These days, I don't even wear a watch, I just use my cell phone to tell time.

I am glad you found the problem but are the fuel pump relays that expensive that you didn't change it while you were at it, or did you already change it before?

[SMWS6TA]

relay works fine, not broken why fix?

[pajeff02]

Hopefully you have this one licked.