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[Help]Lethal Performance fuel system not working

aedfam

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I currently got a lethal performance return style fuel system. I've had the system for 6 months and hardly drive the car. It's not my daily and will sit for a week or so at times.

It features the triple pump fuel hat and 2x Walbro 485 pumps and I'm running E85.

Today while stopped at the light the car went dead (I noticed right before the car died the RPM shot up to about 1500 rpm at idle)... I tried turning it back on but it won't turn over. I also have no check engine light and all other accessories work fine (power, lights, radio, etc..)

The car isn't getting a any fuel pressure (according to the fuel gauge on the regulator) and I don't hear the fuel pumps running when I have the car key-on. I've tried checking all the wiring to make sure connections are good and they seem to be. I have two fuel pumps, will one going bad make the other not work (sort of a safety kill switch)? The fuel pumps are 6 months old.

Has anyone dealt with this issue and/or give any tips as to what to check? My first guess like mentioned above was a bad fuel pump but any other advices/tricks anyone has such as checking fuses, wiring, etc..

I will also call Lethal Performance tomorrow and see if they have any troubleshooting steps aside from check if the system is getting powered, etc..
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Jhalil101

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I currently got a lethal performance return style fuel system. I've had the system for 6 months and hardly drive the car. It's not my daily and will sit for a week or so at times.

It features the triple pump fuel hat and 2x Walbro 485 pumps and I'm running E85.

Today while stopped at the light the car went dead (I noticed right before the car died the RPM shot up to about 1500 rpm at idle)... I tried turning it back on but it won't turn over. I also have no check engine light and all other accessories work fine (power, lights, radio, etc..)

The car isn't getting a any fuel pressure (according to the fuel gauge on the regulator) and I don't hear the fuel pumps running when I have the car key-on. I've tried checking all the wiring to make sure connections are good and they seem to be. I have two fuel pumps, will one going bad make the other not work (sort of a safety kill switch)? The fuel pumps are 6 months old.

Has anyone dealt with this issue and/or give any tips as to what to check? My first guess like mentioned above was a bad fuel pump but any other advices/tricks anyone has such as checking fuses, wiring, etc..

I will also call Lethal Performance tomorrow and see if they have any troubleshooting steps aside from check if the system is getting powered, etc..
The fuel pumps don’t always prime when you key the car on, they often prime whenever you first interact with the car such as unlocking or opening the door in my experience. The gauge on the regulator will blip one time quick when the pumps prime but will go back to 0 psi until the car is actually running. The pumps are wired in parallel so if one goes out the other will still work (assuming they are weird correctly).

You can try jumpering the pumps at the relay and then seeing if you’re getting a fuel pressure reading at the regulator. Alternatively you can pop the hood and have someone else turn the car over while you’re watching the gauge. If it doesn’t move check for voltage at the pump relays and check for a signal from your trigger wire.

I’ll keep my phone on me and try and help best I can, I’m running the same fuel system on my car.
 

Stephen@lethal

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If you are still having any issues installing it, feel free to give us a call or shoot a support ticket over.
 

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Andy13186

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With return style fuel systems the pumps run hard alot of the time. Atleast one is full blast all the time I think. The pumps are in the fuel and the fuel heats up from the pumps, and if the fuel level goes below a certain level there isnt the fuel to cool them down so the pumps overheat. Here is why they are staged usually, and why you should keep the fuel level above half etc.
 

Jhalil101

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Me and op PMd back and forth a lot back when this was first posted and tracked it down to a short somewhere blowing the fuses. Don’t know all of the details but I believe he is up and running. Just wanted to share since it’s gaining attention again.
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