and a brand new opti cause a high rpm miss..i though the opti was causting a miss at idle part throttle ect...put a new one on and now my car pulls perfect to 5000...then it starts missing/backfiring through the exhaust and will barely pull about that...
my car did this before and i found out it was a missing bolt on crank pulley...this time the bolts are there wires are correct and snapped on..is it my opti? or something external?

 

I replaced mu opti, and two days later I noticed an intermittent high RPM miss. Everything else is new(wires, plugs, coil, etc...). I really hope the rotor isn't coming loose in the opti. I've heard stories of brand-new ones having the screws back out. Keep us posted if you figure it out.

 

it was the new opti...went to gm through a mechanic i know and got one for them cheaper than the o'reilley one