I use arco gas but 91

 

what about the spark plug, why is it black? Does that mean it is burning oil? It was not wet just black.

 

second for dead spark plug wires, check with an ohmmeter to confirm.

 

K I'll change the wires and see what happens. Thanks

 

That was the old wire? That does explain a lot. Black plug is fouled because fuel isn't being burned off. That will be a pretty dirty cylinder but will clean up with proper ignition.

I read and article about BP/Arco gas and a lawsuit filed by CA EPA for their dirty fuel a few years back. I would suggest a better gas and see what it does to your MPG.

 

that was a new wire i just put in about two mo ago. It was misfiring with some double platinum autolite plugs from autozone. I swapped those out for some NGK DP with no luck still misfired. But when I swapped the plug the boot was still good. Still misfire so I figure it might be cap/rotor. I changed the C/R about a month later because finances were low. But when I changed the cap and rotor it still mifired; actually sounded and felt worse. Thats when I pulled the plug and saw the fouled plug and burnt boot.

 

Do you have coil packs? I had a misfire on my '91. Replaced plugs and wires but it still continued until I changed my cp's and it went away. Good luck

 

coil packs? well its 5&7 does anyone know if they run off same coil pack

 

yes, you do.

all LS' til '98 had 2 coil packs, one per bank. 5&7 are on the same bank (driver's side, bank 1 iirc).

 

How do you check if the coils are bad?