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hey all this has me stumped, my 34 gtt idles revs doesent miss at all but...as soon you push it on boost it hesitates violently, struggles to make boost and spits out a shi@@load of unburnt fuel black as you know what, i would say it flatspots badlywith absolutley no power on boost. car is running a power fc which i know nothing about, whether its set right or not i would not know.has anyone had this problem b4? any help greatly apprieciated thanx

neil

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  rexrxr said:
hey all this has me stumped, my 34 gtt idles revs doesent miss at all but...as soon you push it on boost it hesitates violently, struggles to make boost and spits out a shi@@load of unburnt fuel black as you know what, i would say it flatspots badlywith absolutley no power on boost. car is running a power fc which i know nothing about, whether its set right or not i would not know.has anyone had this problem b4? any help greatly apprieciated thanx

neil

if you have the powerfc, do you have the hand controller... check things like the TPS voltage when it happens, air mass voltage ect and let us know these values.. also does the knock go right up? or engine light come on?

i have to ask how long have you had the car? it is time to learn the powerfc :no: i have a 34 GTT with an FC if you need some pointers... also read the documentation around the place.

If you know nothing about the PFC its best to leave it to sombody that does. Too many people that have no idea what they are doing decide to play gameboy with the handcontroller and then all sorts of problems come up. ie: engine failure.

Same thing happened with my 33 GTS-T

turns out it was coil packs failing

the way i found out was i pulled my plugs and closed up the gap .1 or .2

If this stops the missfire or reduces it under boost its time for some new coil packs :( and spark plugs to

i'd agree with d_C try check ur intercooler piping. when i first put my cooler on the guy didn't fit the piping on properly n car was fine on normal drivin as soon as it hit boost it just didn't wanna move. went back got it checked out found out the pipin was loose n had boost leaks put it back on n i was one happy chappy again lol

far out thanx guys didnt expect so much help on this, have a feeling its a coilpack or a few on thyre way out. all cooler piping is spot on not blown off or leaking as it is managing to get about 3psi but no more... come to think of it you could call it a severe missfire on more than one cylinder coz thats really what it sounds like while trying to gain boost. as far as the fc goes yes it has a hand controller, no i dont play with it as i know absolutly nothing about it and doesent interest me in the slightest (is actually hidden away under the dash away from curious people) but yea will try and get sum readings off it an let u gurus know , a couple of times the engine light flashed on and off briefly while revving it but didnt stay on, will try a few things and keep you guys posted. thanx heaps!! :)

far out thanx guys didnt expect so much help on this, have a feeling its a coilpack or a few on thyre way out. all cooler piping is spot on not blown off or leaking as it is managing to get about 3psi but no more... come to think of it you could call it a severe missfire on more than one cylinder coz thats really what it sounds like while trying to gain boost. as far as the fc goes yes it has a hand controller, no i dont play with it as i know absolutly nothing about it and doesent interest me in the slightest (is actually hidden away under the dash away from curious people) but yea will try and get sum readings off it an let u gurus know , a couple of times the engine light flashed on and off briefly while revving it but didnt stay on, will try a few things and keep you guys posted. thanx heaps!! :)

  rexrxr said:
far out thanx guys didnt expect so much help on this, have a feeling its a coilpack or a few on thyre way out. all cooler piping is spot on not blown off or leaking as it is managing to get about 3psi but no more... come to think of it you could call it a severe missfire on more than one cylinder coz thats really what it sounds like while trying to gain boost. as far as the fc goes yes it has a hand controller, no i dont play with it as i know absolutly nothing about it and doesent interest me in the slightest (is actually hidden away under the dash away from curious people) but yea will try and get sum readings off it an let u gurus know , a couple of times the engine light flashed on and off briefly while revving it but didnt stay on, will try a few things and keep you guys posted. thanx heaps!! :(

be careful cause the engine light might be comming on due to knock which can turn out very bad if it happens too much.

  rexrxr said:
hey all this has me stumped, my 34 gtt idles revs doesent miss at all but...as soon you push it on boost it hesitates violently, struggles to make boost and spits out a shi@@load of unburnt fuel black as you know what, i would say it flatspots badlywith absolutley no power on boost. car is running a power fc which i know nothing about, whether its set right or not i would not know.has anyone had this problem b4? any help greatly apprieciated thanx

neil

I would be checking for fouled spark plugs mate.

I'm hoping the pfc is tuned as well and not just been installed?

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