Fuel Pump Wiring

[Blitzdvr4]

Trying to diagnose my no start/no fuel problem. Along the way, I opened up my fuel pump area on my VR4, and lo and behold this is what I see. I know you guys rewire your pumps, but is this a bad hack job or what is this?

 

[3kgt2nv]

try to get the pic uploaded. nothing is showing

 

[Blitzdvr4]

thanks for the note.

 

[BrokenTsi]

Is this a car you just purchased? When was the last time it was running?

 

[3kgt2nv]

where that spice is there should be a power wire. most likly the previous owner rewired it for more voltage and it has been removed. go to vfaq.com and look up the fuel pump rewire and perform that and it should be good to go.

http://www.plymouthlaser.com/rewire.htm

 

[BrokenTsi]

That's exactly what I'm thinking. The black/white wire is a power wire for the fuel pumps. I was trying to see if there was more to this story.

 

[Blitzdvr4]

i've had this car for a little over a month now. honestly speaking, it was running pretty good.

-I replaced the isc two mondays ago as it experienced idle problems. at this point i ran codes just to see (although no CEL was on), and got codes for 31 (knock sensor), and 44 (ignition). Car ran fine..idled well, adjusted the idle couple times and it pulled smoothly.

-this past friday, it stalled on me all of a sudden (no CEL), and couldn't start her up again. went through the car, trying to figure it out.

-noticed i had no spark and no fuel. no CEL, ecu threw out no codes, the multimeter needle just moved back and forth.

-had friend test the CAS, he thought it wasn't reading right. got a CAS and another ECU from reported running cars, and threw them on. Got spark, but no fuel.

-friend told me he noticed that the MPI relay was not closing one of the sets. I looked at the pins and noticed one of them seemed burnt.

-changed out the MPI for one from a reported running vehicle (have not been able to test the relay yet). no start, however the battery was cranking at under 10volts. had to go to work and no time to charge it. this was earlier tonight.

-decided to take some pics of the fuel pump just to see what I'm working with here, and that is the pic. I really have no idea about this pump and rewiring, just seemed strange to me.

-going to charge up the battery tomorrow and go at it again to see what's going on. any suggestions would help.


i dont know what to make of that ecu wiring madness below...there is one small part of black/white wire that is exposed from the small plug on the right.

pic below is circling which pin on the mpi relay seemed burnt a little- had some white on it.

 

[pauleyman]

You don't need to go to that much work to test the fuel pump circuit. Jumper the test connector under the hood. You would be able to hear the MPI relay click. If you don't start there. If you do go find the voltage at the rear of the car. Even if it's rewired unless the previous owner clipped it there should be power at the harness and that would be used to trigger a relay. Your shot is too close to see what goes where. Looks like more than one wire cut but I can't tell where they go. If you previously had a code 44 you could have an issue inside the ecu. Code 44 is sometimes one of those tell tale codes if there is ecu damage. But first I'd check that fuel pump circuit. Whole thing shouldn't take 10 or 15 min.

 

[Blitzdvr4]

You don't need to go to that much work to test the fuel pump circuit. Jumper the test connector under the hood. You would be able to hear the MPI relay click.

which is this test connector?

never mind, i figured out it's the small connector on the firewall. I'm supposed ot just attach a cable from it to the positive terminal to see if the fuel pump will work, correct?

 

[pauleyman]

yes, Just make sure you have the right connector.

 

[Blitzdvr4]

finally figured out what was wrong. prev owner rewired the fuel pump but put the 20A fuse in the back near the fuel pump and behind the side trunk trim which I didn't see til tonight. the fuse was blown. there was a tiny blue fuel filter on top of the fuel pump which I imagine was clogged as well as the main one which probably made the original pump overwork and blow the fuse. I replaced the fuse and it started right up.

going to replace the filters, and put the fuse up next to the battery over the weekend...so glad this is over.