Put the new transmission in and went around the block to make sure the fluid was at the right level in the transmission and I noticed something didn't seem right and I seem to be backfiring. Got home and realized the cylinders # 2 and #4 on the passanger side are not firing the spark plugs look brand new (which they are).

The header tubes where clean nothing on them.(New headers) the rest were black/brown. Spark plugs too, silver and shiny the rest looked fine.

Spark plugs and wires are new but again car has been sitting. (NGK TR6 plugs and Elite spark plug wires)

The opti doesn't have a lot of miles but it is old and has been sitting a long time lately.

Coil wire had some white corrison on it at the coil. I am going to replace the coil regardless it is old and the corrison bothers me.

Should I replace the coil wire and opti as well. I hate to do the opti unless I have too. Anything else to look for? Could it be something else?

Thanks for any help or insight as to what the problem might be.

Mod list below: 96 impala ss, 383 Forged stroker, forged eagle crank, eagle forged H-beam rods, Forged SRP -16cc pistons, LE2 heads, ported intake, custom cam, CSR electric water pump, GMPP 1.6 RR, 58mm throttle body, custom/RAISS dual intake, Mallory hyfire 685 ignition, TNT nitrous kit, NGK TR6 spark plugs, Clear image Budget headers, elite spark plug wires, pypes x pipe, summit race mufflers,3.73 gears

 

its possible that the two wires are switched? i had 2 and 4 switched and the car wouldnt even start. When it did it ran bad, It would backfire in the intake once when turning over ..... both of those primarys were cold.(meaning no fire)

 

I dont think so, it ran decent just something was wrong rough idle and bad performance.

I will double check the spark plug wires though. Thanks