Well to no avail and my discouragement I am at a total loss at this point troubleshooting this problem. A quick back story. Few weeks ago my engine randomly cut out while cruising on freeway, lost fuel pressure. Found the float arm on the fuel pump basket somehow broke off and created a break in the circuit loop so I guess ecu wasn't telling pump to come on. I luckily had a spare basket and swapped in getting the car back on the road, however the old float arm was lost in the tank, couldn't see it and couldn't find a way to retrieve it, so i left it in there and crossed my fingers, thinking no way it would find its way into the fuel pump containment area and probably wouldnt matter if it did anyway.

Well today again on freeway I lost the fuel pump again wtf! Got car towed home and found the old float arm in the contaminate area playing with the fuel pump basket, and no idea how it managed to get in there but it did and have to think it has somehow caused this current issue, I dont know how or what but seems too coincidental that its unrelated.

Things ive done/

*Checked every fuse on the car, all good
*Checked the main pgi relay under dash, all good
*Checked the SOS rewire relay in the trunk, all good
*Checked the fuel pump, wired strait to batt, works fine and swapped in good working stock fuel pump to basket and tested, not working

No external signs of anything burnt or broken/out of the place on the fuel pump basket. I'm at a total loss at this point on where the issue is or what to check for. If anyone has any ideas Id really appreciate it!

 

So the fuel pump is not priming right now?
The float or fuel level sensor shouldn't have any impact on this at all, it just sends fuel level signal to the dash.
Are you using stock ecu and is it sending signal to main relay to power the pump?

 

Correct

You wouldn't think so, but as mentioned I seemed to have discovered that there is a connection there to the ecu, so when the arm busted off the plastic and metal readout on the basket, it caused the system to die. Swapped a good basket back in with no other changes and wala. Also a note to make on this, after swapping that good basket in and got the car to run, the fuel readout was not reading until I re set the ecu.

You are talking the main PGI relay under dash? Yes, this is good.

Thanks for chiming in.

 

Hey Junky,

Im not familiar with your rewire, but I'm guessing the pump still uses the basket ground?

When you replaced the basket, the single wire half spade connection, did you re-pinch it to ensure its tight?

I didn't when I swapped the Walboro in a few weeks back, and wasn't priming either, pulled it and repinched it so connection was solid. Sorry if this doesn't pertain to your rewire

 

Hey thanks for chiming in. The rewire is the Science of speed rewire kit for improving the voltage from factory wiring when running a aftermarket pump. This portion is all working/checks out.

But it seems like in general could be a ground issue, just not sure where as all grounds look in place. Per your ground question, the one ground wire mounted to outside of basket stays in place/doesn't move when swapping the pump in basket, and rest of the connection is just pnp, so i'm not quite clear on what round/connection that came lose you are describing. At this point I decided to just get another fuel pump basket and swap it in and hope that solves it again this time and be done with this. Should be here this week and will report back.

 

It shouldn't be that hard to measure where the problem lies if you are electrically inclined.
When you write "all good" that doesn't mean anything for me, other than it still there and hasn't being burnt up maybe
I'm happy to help but you need to be much more detailed on what has been tested or checked.

 

Hey thanks I appreciate that. To add to the list of what I checked on the op. This may further narrow it down for you. I get normal 12v priming operation measured at the plug to fuel basket when turning on ignition, so that tells us everything is good at the end of the chain. But when I plug it in to fuel basket I get nothing, dead. As mentioned previously this was the exact same scenario as when the float arm tore off the basket damaging/breaking the circuit loop which created an open. Replacing with a new basket solved the problem. This time the basket has no signs of damage and I find it a little strange that the broken arm even making contact with the new basket would have any detrimental effect. If anything wouldn't it just create another grounding effect? I don't know. But it hasn't caused any visible damage which makes me a little apprehensive. I just hope that didn't cause some portion of my ECU to fry.

Troubleshooting electrical is not my strong point, no. But have had a few friends who are coach me along the way to this point. Everyone is stumped at this point so am reaching out here in the off chance someone might have an idea I can check for besides my list ive already done. Replacing the basket with another seems like the next logical step considering where we are and how cheap I can get one. If that doesn't solve it, im up shit creek though at this point.

 

You are using a high amp pump right?
I've seen a few occasions where the high load melts down the connection on the basket, if you are using cheap ones maybe they break even faster.
Have you tried measuring the resistance between pump connection and the top of the basket?
I'm trying to think of a way how the fuel level circuit could have an affect on the pump but can't see it.

 

You said you tested PGM Relay though already.
When you prime, can you measure 12v+ off the SOS relay out? If not the coil is not closing on the SOS relay, which should be triggered by the ground from ultimately the ECU.

 

Just a typical AEM 320. The connector plug to basket is oem, however the main voltage wire and ground were re pinned in that connector per sos for sake of improving the gauge, but those wires again is getting good 12v as it should at plug and ground wire looks fine/secure. When it comes to testing ohm, I don't know what i'm looking for or even the proper setting on my meter so we deduced around that so far as it wasnt a factor in the last scenario. To add for what its worth, I swapped in a oem fuel pump into this basket and still got nothing. The AEM pump also works fine tested direct to battery.

We were too initially, we figured it has to be tied to the factory ecu programming since that fuel read out is seen by the ecu.