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Hey guys, I'm new to the forums and was just wondering if I can get help with something. I am aware there is a lot of information on the site already but none of it is exactly the problem I am experiencing. Basically I bought my series 1 R33 gts25t about 4 weeks ago and it has a 3 inch exhaust, pod filter, intercooler, boost controller and boost gauge. When I bought it, the boost had been set to 9ish psi, and was running fine however the previous owner told me he had been running 12 no problems. I changed the pod filter as it was extremely dirty and the oil to semi-synthetic oil. Anyways after the first week or so I decided to boost the car up a bit to 12 pound. It was running fine in the extreme heat wave for 2 weeks (I live in Adelaide :)). Then a couple nights ago it cooled down and while driving along I found my car began misfiring at around 3000-4000 rpm, it doesn't seem to be at an exact RPM just in that area. The problem also only seems to happen in 3rd and 4th gear and when the throttle is pressed all the way down. I turned the boost back down to 9 psi and it continued to happen. Today I decided to turn the boost right down to 6 pound and I disconnected the battery to reset the ECU. On 6 pound the problem seems to have stopped, but even putting it back up to 8 pound it still does a huge violent misfire where the engine seems to cut out for half a second or so then kick back in around 3-4000 rpm in 3rd and 4th under full throttle (as previously stated). I have checked for leaks and found a rubber seal for some sort of oil pressure valve maybe, that goes into the engine cover, had been destroyed, I replaced it however and the problem has not been rectified. I am now running 7psi roughly, just so the car doesn't cut out until I fix the problem, I was thinking maybe it is the R&R setting the ECU has, but I didn't read anything about it only happening in 3rd and 4th gear and I don't understand why it wasn't happening before but all of a sudden started now. Also, even though now it isn't cutting out on 7 psi, it still does feel like its struggling under heavy acceleration/load in 3rd and 4th gear, etc, and when the engine turns off I can hear a lot of vacuum/air being released out of the pod filter for about 10 seconds and other areas I can't pin-point (this has been happening since this morning when I replaced the little rubber seal that goes into the engine cover, however I don't see how it would make air leaking noises from various spots in the engine bay...) If anyone has any ideas on my issue any help would be much appreciated, and thanks for taking the time to read this whole post. Cheers, guys. Steve.

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