1bad03snake

iTrader: (16)

I bought a SSP wiring harness w/ fuse box and had it in my 91 coupe/4.8L After about a month and a few hundred miles I would get an intermittent miss. I used a temp gun and my driver side bank was cold ( the car was running on 4 cylinders) I messed with the fuse box wiring and everything lined out. So after 5 months of building an 88 coupe with a 6.0L I reused my old harness and after about 20 minutes of idle time the same problem is back.... Any suggestions? I found a loose wire from the fuse box to fuel pump. I fixed that but I'm pulling my hair out over this issue.

Old Geezer

iTrader: (3)

Sounds like it's time to unwrap the harness, and do a once over of all splices, crimps, connectors.
A problem at the fuel pump wiring should affect all 8 cyls, not just 1 bank.
Since the prev issue, + new pump issue, go directly to the fuse block, maybe replace that item, then work from a known good starting point??

usdmholden

Time to start diagnosis. Do the coils have 12V power measuring with a multimeter? If you put a screwdriver in one of the plug wires and position it near the engine does it spark to ground? Are the injectors firing? Listen with a long screwdriver touching an injector and the handle end in your ear. If it's the whole bank not firing it sounds to me like it's a power or ground problem instead of an individual cylinder problem.

1bad03snake

iTrader: (16)

The fuel pump issue is fixed. I re-crimped the connector and plugged it back last night. The whole drive side has no power. No spark or injector. I used a noid light on the injector and used a screw driver in tje plug end to check spark. Im going to check grounds and swap relays around

BP Automotive

iTrader: (3)

I do not know how they build their harnesses, but it sounds like you have one of two issues,

the bank 1 splice is no longer conducting, or the circuit supplying bank 1 with power is no longer conducting.

Im sending you a PM...

1bad03snake

iTrader: (16)

Replied to your pm

Thanks you for everyone's help.

LS1MCSS

iTrader: (18)

You shouldn't have a relay supplying power to the coils/injectors on one side. It should be a 15amp fuse.

1bad03snake

iTrader: (16)

When I get off i'm hauling *** to sears picking up a few things then i'll mess with the car for a little while tonight.

87lsttop

iTrader: (2)

Hope you get it fixed. I need to come by and check it out when I get back from out of town. Maybe get some pointers out of your build for mine