So some back story. I have a 2002 R53 with 90k miles. Engine related modifications are intake, 15% SC pulley, shark injector tune, Alta v2 intercooler.
When I drive in first, I can accelerate as fast as I want. When I shift into second, if I have the throttle more than half way down, it starts to bogg, then goes into limp mode and runs on 3 cylinders. I then get a cel, and it says p302 cylinder 2 misfire.
I turn the car off, and right back on, and it runs fine again. It is throttle dependent, because I can rev high through the rest of the gears just fine, as long as I don't go more than about half throttle.
I moved injectors around, and it's still #2. Piston ring? Burned valve?
I removed my sprint booster thinking maybe some programming error, didn't fix it. I then replaced the Ignition coil and spark plugs, and still nothing.
Someone had mentioned that it could be a failing Crank Pulley. I do smell burned rubber after I drive, but i dont know if that is just my tire rubbing on the wheel well.
Any help is much appreciated.

 

Check out these threads below for some possible ideas to track down your issue.

https://www.northamericanmotoring.co...2-misfire.html
https://www.northamericanmotoring.co...15-pulley.html
https://www.northamericanmotoring.co...the-cause.html
https://www.northamericanmotoring.co...2-misfire.html

 

Bet the shark injector advanced the timing, and burnt a valve....all too common.
Get a compression check....both wet and dry...bet ypu $5 it is a valve issue.