Under Load Misfire Problem

[Caaal]

Hello, SAU

I'm after some help regarding my stock 1995 Nissan Skyline S1.5 ECR33 GTS-t.

I was having a misfire problem and finally diagnosed that it was being caused by a failed injector (no. 1). It turns out the previous owner had set the injector duty cycle to 100% on stock injectors via the PowerFC. This of course destroyed the injector and leaned out the engine; thankfully it didn't totally destroy itself. After sending my injectors away to be reconditioned I reinstalled them. I was sure to clean to fuel rail as well. I also swapped out my PowerFC with a stock ECU as well as checking the coilpacks. Coilpacks were all firing nicely even at high RPMs.

Upon getting the car started I took it for a drive around my street after letting it warm up for about 15 minutes. It idled perfectly, but when I opened it up it misfired chronically above 4K RPMs. Parked it back up and checked to see if all the injectors were working. All were clicking nice and fine except for cylinder 5's injector which would stop clicking above 4K RPM. I'm at a loss at what to do because these injectors were just reconditioned and the plugs are all clipped in properly.

Was thinking that the problem could possibly be grounding as the battery has been relocated to the boot and the main ground for it in also in the boot. I've also checked and scuffed up all the grounds inside the engine bay.

Has anyone experienced this kind of problem before and maybe point me in the right direction. I'm new to the import game

Any help would be much appreciated

[niZmO_Man]

Tried a different AFM and CAS?

[Caaal]

I've tried a different AFM, but haven't tried a different CAS.