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The title says it all..I dont know WTF is going on, I hit 3rd gear WOT and at 5800-6000 rpms the car seems to misfire and break up for a second then pulls through it.If feels like a rev limiter kicking in..
Here is what led up to it..

1-installed a J&S safeguard incorrectly and thought I fried my ECM
2-purchased and installed new ECM at Nissan..Turns out it was a $2 relay...
3-re-installed J&S correctly this time...
4-raced an SVT COBRA and the car stumbled in 3rd gear..Won anyway..
5-put in new plugs,still stumbled..
6-bypassed J&S and put 7lb pulley back in-still stumbled..
7-completely removed the J&S and it Still did it..
8-new plugs,regapped from .035-.030- still stumbled..
9-tried to put the original ECU in but car wouldnt start.I guess its immobilized..
10- swapped out MAF sensors, still stumbles...

I can say without certainty that it is NOT the plugs,gap,or the J&S that is causing it...But on a weird side note, I went to change my oil today and only had 1QT!!!!
Hopefully I didnt damage any internal just yet..But I see NO smoke of any color ever come out of my car...and it runs like clockwork till I hit 5800 rpms...Weird.I kind of suspect that POS STEALIN oil cooler as the leaking culprit..
Gonna try to replace the coils tomorrow if thats not it I dont know WTF to check other than the ECU...But I get no misfire codes...
 

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****, bro. That sucks. I started thinking of easy things off the top of my head like fuel pump, MAF sensor, crank angle sensor, O2's, etc. You are way more mechanically inclined than I am, but the only advice I can give you is use process of elimination (which it looks like you started) and check the easily overlooked parts first. Maybe you have a loose connection or maybe a completely disconnected sensor. I hope this gets you looking in the right direction! Good luck!
 

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Daking350Z,

I am far from an expert but here are some thoughts: If you are still running the ProCharger with the Aeromotive DFMU and Aux fuel pump. Check for vacuum/boost leaks. A vacuum/boost leak could cause a rich mixture at low rpm and a lean mixture at high rpm. The DMFU controls the aux fuel pump using maifold boost pressure, with a boost leak past the MAF (like the intake manifold) would fool the DFMU into thinking the boost is lower that it is and it will not provide the voltage to the aux fuel pump to provide the pressure needed to provide enough fuel for the right mixture. Of course check the vacuum/boost hose/line to the DFMU, if its leaking it will have the same effect. Check the fuel pump to make sure it is providing the pressure. Check the DFMU to make sure it's providing the right voltages to the fuel pump. I would think that this would cause an MIL and error code.

Good Luck, let us know when you find the problem.
 
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