Idle Problem On R33 Gtst

[Slapstik]

Hi Guys,

Got a problem which has reared it's head in the last week. Car idles extremely rough, sorta like a high RPM missfire. hard to explain, but sorta sounds like a WRX (constant pop) and the whole car shakes badly. Car got tuned around 6 months ago.

has Power FC, Z32, 850cc sard's, Splitfire coilpacks, HKS twin spark, upgraded turbo and external gate and Walbro Fuel pump with re-wired relay.

Swapped out the coilpacks with a brand new set as a precaution, regapped plugs to .7 to rid it of any chance of missfire. Changed fuel pump relay, changed Coil pack loom and swapped Ignitor pack.

Checked the Z32 wiring tonight and noticed that going by PaulR33's wiring picture that when the AFM was installed, the signal ground and 12v ground were mixed up. swapped them and the same problem remains. What are the odds of this mix up causing an AFM failure or PFC failure?

Only thing i haven't done is swap the fuel pump over, sounds a little funny when it's priming, but was looked at by a mechanic and he said it was working. another possibility??

Any help is much appreciated.

Cheers

[mitchum]

Hi Guys,

Got a problem which has reared it's head in the last week. Car idles extremely rough, sorta like a high RPM missfire. hard to explain, but sorta sounds like a WRX (constant pop) and the whole car shakes badly. Car got tuned around 6 months ago.

has Power FC, Z32, 850cc sard's, Splitfire coilpacks, HKS twin spark, upgraded turbo and external gate and Walbro Fuel pump with re-wired relay.

Swapped out the coilpacks with a brand new set as a precaution, regapped plugs to .7 to rid it of any chance of missfire. Changed fuel pump relay, changed Coil pack loom and swapped Ignitor pack.

Checked the Z32 wiring tonight and noticed that going by PaulR33's wiring picture that when the AFM was installed, the signal ground and 12v ground were mixed up. swapped them and the same problem remains. What are the odds of this mix up causing an AFM failure or PFC failure?

Only thing i haven't done is swap the fuel pump over, sounds a little funny when it's priming, but was looked at by a mechanic and he said it was working. another possibility??

Any help is much appreciated.

Cheers

start with a compression test...

[Slapstik]

Changed out the Fuel pump to a Bosch in-tank. Problem solved.

Cheers