rb20 runs rough won't rev past 3k rpm

[R32RB20]

My Rb20det (r32 skyline) starts as soon as the key turns but it's running rough and has no power or acceleration especially when climbing hills. I notice the following symptoms:

- rev limiting (fuel cut) @ approx. 3000rpm sometimes lower on higher gears

- idle is steady

- when afm is removed doesnt go past 2500rpm

- in neutral only revs up to 4500rpm

- strong smell of fuel from exhaust

- no change to engine when removing 1 or 2 ignition plugs 

- got a code 21 error and sometimes the exhaust temp sensor light will flash briefly 

 

THINGS I'VE DONE TO RESOLVE THIS: 

- replaced fuel pump (Walbro 255) but its really noisy.

- replaced filter filter

- cleaned afm with brake cleaner

- changed ignition coils to r35 (vr38dett)

- as per above removed coil ignitor

- flushed oil and radiator, but both are leaking

- checked compression, avg. 225psi each cylinder

- sonic cleaned all fuel injectors (fixed one leaking and one with bad spray pattern)

- fuel pressure approx. 40psi (aka 3kg/cm3)

- replaced iridium plugs with copper and gapped to 0.8mm

 

all stock, except 3inch turbo back exhaust, and ignition coils/igniter 

 

Any help is appreciated. thank you

 

[CanadianGuy]

I just finished fixing a similar problem on my rb20, I’d double check your AFM or the AFM wiring. Mine didn’t have 12v on the power wire, as soon as I ran a jumper wire it ran perfect. 
 

From my understanding there’s very few things that will induce that cut from the ECU so I’d be looking at the AFM for sure. Walbros are loud pumps so wouldn’t be too worried about that and it seems like you’ve checked the majority of the other spots

[R32RB20]

thank you I'll pull it out later today and have a look