RB25DE RPM drop off

[dirtyjuan]

RB25DE RPM drop off

Ive just picked up a stock R34 GT-V with a Fujitsubo legalis R exhaust as a daily and cant fault it except for a drop of power when climbing any kind of slope (downhill fine) between 2500 and 3500, and is noticeable when minimal throttle is used and im just gradually gaining speed. It will happen most times on the same road but not always depending how I throttle it.

It will hit 2600 and drop by as much as 400rpm and then picks up again. Sometimes it happens up around 3200-3500 but minor. Other times it will happily climb a very steep hill in 4th and theres no sign of it. It starts perfect, idles great but a bit high at 800. 

I have reset ECU, checked and replaced vaccum hoses all around top of motor and cleaned AFM with no change. I plan to do plugs in a few weeks and eventually splitfires but im hoping someone can point me in the right direction as I have very little knowledge on the NEO and find its a pain in the arse to work on compared to my RB30. Thanks