BoostFrenzy

Is this "ignition breakup"? I have did the plugs but not the wires, car has K&N filter / chopped airbox / downpipe, boost pattern is 11-8-10 but by 6500 where it stutters (it's VERY slight but noticable), it's more like 9.0-9.5 back and forth

RX7Wishing

check your check valves. The reason i say this is because i had ignition breakup issues likes yours @ the same RPM and my issue was a checkvalve that was reversed. Don't ask me why it caused break up. But hey.. it fixed it.

BoostFrenzy

hmm... which check valve was it? i already swapped the one out on the pressure tank, checked the one to the vacuum chamber

RX7Wishing

it was the one behind the(next to the firewall) the UIM and under it. I had to pull off the UIM to get to it :T

BoostFrenzy

ah i'll check it, it started after i installed the bosch universal o2 sensor but that shouldn't matter

BoostFrenzy

Plug wires seems to have resolved it, however, now the car feels slower because the power is so smooth I need to check the boost pattern again, one of the leading wires was twice the resistance as the other (within spec but prolly outo f spec warm)