hi all just joined today looking for some advice my cars a 96 wrx import running a straght through exhaust after market dump valve and a induction kit (piperx) when i boot it it gets to 5000rpm and starts to jerk but sometimes cut back in it even made it backfire tonight seems to do it in every gear is it over boosting and the fuel cut off is kicking in or is there other gremlins lurkin???

 

What boost r you running mate? I had the same prob running 16psi, i turned it down to 12 and now she is completly different...

 

some other bits i did where...cleaned the little sensor in the air intake (its the air flow sensor)
checked all my boost hoses for leakes, had a small one on the line to the boost gauge

 

runs round to one bar on the gauge really annoying me

 

have you tried putting on the OE recirc valve , is it a big jerk

went in a car which hit fuel cut and nearly went through the window - my faulty vta caused rough bump ride as you let off the gas

plugs \ coil pack maybe

 

1BAR IS ABOUT 14PSI ISNT IT?
well all i can think mate is check everywhere for air leaks, (all boost hoses and the gauge hose).
then clean the airflow sensor (be very very careful) is is easy to brake.
try turning the boost down a take to around 0.8 bar and see if it still does it.
If you have a dump valve, just try the car without it, it may be leaking under high boost.
apart from that mate I dunno, i bought a fcd but never fitted it cos i heard horror stories

 

fuel cut on your car comes in at 1.05 bar boost so its very possible that you could have that

the other thing that causes this problem on your model car is the coil packs, take out the coil packs and pull the rubber boot off the end of them.
if the ends are cracked or broken off this is the problem.

hope this helps

 

oh and 1 bar = 14.7 psi

 

thanks guys for the help think it os the dump valve taken off and it boosts fine was some stpid twin trumpet thing all good now just need to buy a recirculating one now