msd
#3
I wouldn't say it usually doesn't help. When I did mine, and after looking at the crap in the cap, I'm fairly confident a cap and rotor change would have cleared up my bad running engine. The opti works by the same principle as an old school cap & rotor ignition. Going to 100k miles without a cap & rotor "tune up" would be unthinkable.
But, considering I had almost 100k miles on the opti unit itself, and the big pita it is to get to it, it made the most sense to just replace the whole thing and start out new.
But, considering I had almost 100k miles on the opti unit itself, and the big pita it is to get to it, it made the most sense to just replace the whole thing and start out new.