Trying to help a buddy with an LS swap '57 Chevy.
Junkyard 04 GTO LS1
UPDATE
Car refuses to idle and still backfires. I logged misfires by cylinder and see a large number on #7 and some on #2. Plan to replace coil on #7 and swap injectors and coils if that doesn't remedy.
Fuel Pump replaced after observing erratic fuel pressure drops at rail...now holds 58psi as expected
Did verify via noid lights, all injectors are getting signals from ECU
Plugs and wires have been replaced with OEM wires and TR5s
MAF replaced
TPS Replaced
Cam sensor replaced (this allows the engine to at least run now from 1500-5000 without stumbling or backfiring)
Removed and reinstalled intake (to swap cam sensor) and made sure intake gaskets were intact and manifold torqued correctly.
Would misfires like this cause the engine to backfire horrendously at idle? Anything else I'm missing, am I still chasing ground gremlins?
This thing is really frustrating me to say the least.
Latest Logs and Tunes attached. Really appreciate any help!! Cool car just need it to run! Been almost 10 years!!
On first start, the motor ran horribly, backfiring and barely idling.
B1 (Driver's) is showing Super Lean and then spikes of fuel.
Here is what I know and the data I have:
PSI - LS Swap Harness
PSI - EFI Tank 255LPH Pump
PSI - Gauges
04 GTO Complete (Tune File and Scan Attached)
Injectors were cleaned and flowed by Injector RX
Fuel Rail was dirty and cleaned by injector RX
Corvette Style Filter/Regulator
When I first plugged into the car I couldn't get any data - realized the only grounds that had been connected were to the block and the PSI harness to drivers cylinder head.
Ran all the grounds per PSI tech sheet using correct AWG, hydraulic crimps, sanded surfaces, star washers.
New battery
Not sure why B1 is so lean and only randomly delivering fuels spikes.
Plan to go get Noid set next.
Why don't I see Duty Cycle or PW on injectors?
Thanks in advance for any help!!