bucking problem S14 SR

[EJ253]

ok, so after a drift event a while ago, my car started to buck like it wasnt getting spark (which may be possibly be the problem), but i've changed the plugs 3 or 4 times and the problem is still happening. right now im running NGK iridium 7s

when the plugs are bad it bucks at full throttle (on boost)
but right now, what its doing is bucking at anything but full throttle
once its on boost at WOT it does ok, altho the turbo does seem a little bit louder than before.

my friend nick suggested that it may be a vacuum leak but i cant seem to find any problems. im going to replace the couplers because they're all shit.

does anyone have any suggestions or advice?
it would be greatly appreciated.

the car is track only now, and i either understeer or spin out because i cant give it 50% throttle. its getting annoying and i have a big event at MMP on nov 3rd that i'd like my car to be fixed for.

thank you very much

-Greg

[skylindrftr]

you can do a vaccum/boost leak test, there are tuts on it somewhere around here but basically you get a air pump or compressor, block off the intake and put a tire valve there, put engine at tdc (so no air gets in the engine) and put air into it, you should be able to hear it if it is leaking from the charge pipes, intake manifold or vacum lines, also keep a boost gauge around to see if it is holding pressure.

[EJ253]

i'll try that. thanks a bunch!
does anyone have any other suggestions?