I have a 95 Z28, 72,000 miles, not much for hop-ups....underdrive pulleys, K&N filter, Hypertech computer programmer, flowmaster exhaust, fresh tranny....the car began to miss a few months ago so I had plugs and wires replaced and the miss went away. Don't drive the car much but not long after that I spun output shaft in half in tranny and had to have it rebuilt. Third day home from rebuild, car missing worse than ever.....mostly under load. Returned to mechanic to find shorted plug wires ( he used crappy set, routed them poorly) new Delco wires now, but still missing....seems to be getting worse.....I have heard that shorted wires could mean fouled plugs, and also have heard could be bad Opti please respond and let me know what you think, thanks in advance, Ed

 

Bad opti could be the case. GM recommends changing cap and rotor and peripherals @ 100k miles. You say your car only has 72k, but since it's Opti spark (known to be crap) change it out if you haven't already, you eventually will.

I changed it on my 95Z28 when it was miss firing and weak on power, after that, car runs fine. I would recommend getting an Opti from MSD.

p.s. Plug wires were a pain in the *** to rout the way they came from factory, but for sure they have to be routed correctly, otherwise that may also result as a problem.

 

thank you for your input, I am very appreciative. I have an appointment this Tuesday to put it in the shop. I think I will go ahead and replace the opti....I have heard a lot of negative feedback about the MSD, what has your experience with it? Oh by the way if I replace the Opti, does it come with cap and rotor? I am leaning toward Accel, or OEM replacement, what are your thoughts.

 

Every one that i've ever talked to have said that the accels are complete crap... I acutally have heard alot of good about the msd's. I went with Ac Delco. Don't get just the cap and rotor, get the whole thing.

 

I think it's OEM for me. I saw a few comments about O-ring vs. gasket, can anyone clarify this procedure....best practices.....other work to be done while Opti is being replaced?