I have a 2002 that I pulled the engine and rebuilt with S3 comp cams, edelbrock intake, K&N filter, holly injectors, high compression pistons, balanced crank and new exhaust manifolds. I have a programmer and have eliminated the O2 sensors as the new exhaust manifolds do not have them. I installed new coil packs and plugs before the work, although the coil packs are aftermarket.

In the first couple hundred miles all ran well, but then it acted like a coil pack or two was dropping out...

Engine won't run right after performance improvements