Max78

Ok,

I was driving around one day on the way to the gas station and I took a corner too fast and starved the pump of fuel temporarily, it didn’t stall but sputtered. I have done that way to many times because ¼ tank is not empty right?

So after that happened it starts acting strange. My AFR is higher than normal but still runs good. I fill it up at the pump and start it and its missing and sputtering, my AFR goes from 16-19 over the next few minutes and it has no power, I figure I killed my pump. I get it towed home, test the fuel pressure and its getting 10psi. I remove the fuel filter and check to see if it’s clogged, it’s still good. I test the fuel pressure again and now it will only build up to 5psi and instantly drop to 0 after the pump shuts off. I clamp the return line and same thing. There are no leaks in the system.

So I go down to the local hotrod shop and buy a new Walbro 255 and install it. Same problem!!! After installing the new pump I listen to it and it sounds just as week as the old one. So I test the voltage at the pump and my fluke reads 14-12 volts at the pump.

I plan to bench test both of them today after work to see how well they perform hooked directly to the battery. . . If it is a voltage problem are there any common areas too look?

Anyone have any ideas?

fleetmgr

Have you checked the FPR?

Max78

I clamped off the return line and it made no difference.

hrcslam

Voltage alone doesn't power make. Just because you have 12-14V doesn't mean you are getting the amps you need to run it. You need to load test the connection. If it checks out good to the plug, then check out the connection from the plug to the electric motor.