Robs been over with car today.
Car is boosting, but it's like it hits boost or fuel cut at around 3500 4000rpm. The revs just drop off like it's been turned off almost, then come back in once they have drop by about a 1000rpm.
We've ruled out map sensor, spark plugs, coil packs and ignighter.
Wiring looks to be right.
Sensor for temp gauge appears to be dead and just giving a max temp reading all the time.
I'm thinking that it's possibly the ecu water temp sensor that's the fault but not 100%
There is also a bit of a misfire all the time.
Anyone got any ideas of posable cause?