r34 gtt misfire at 4000-4200 rpm

[wabbit75]

herro

r34 gtt

had the car for a year running like a dream. then nek minute, it runs like a three legged dog

so at 4000 - 4200 rpm and only then and onward  it misfires but up to then it runs perfect  .. 

it has brand new coils and plugs   tried another m.a.f

only thing done too the snot box is a gfb electronic boots controller  set to 10 psi max

disconnected it put it back on the duel stage solenoid.  same thing happens  but only will produce 5 psi max .. feels very slow .. v dub beetle would kick its arse haha

thoughts are boost sensor or c.a.s.  but have wizzed the multimeter on getting correct readings.  

engine light is not on

like i say been running perfect with no mods for this to happen 

see if anyone has some thoughts cheers    

 

 

 

Edited January 13, 2019 by wabbit75
forgot car make