91 PA idles rough

[JoeNezz]

Hello
I have a 1991 PA/ultra & it just started idling rough today & is slow to accelerte.

I have just changed the plugs & wires.
when I changed the wires there was rust in two of the boots when I pulled the ends off the coil pack so I cleaned the terminals good before I put the new wires on but it made little difference in solving the problem.

I checked for trouble codes but none were stored & no SES light has ever come on while driving or at idle.

Does anyone have any ideas as to what might be causing this?

Thanks in advance, Roger

[HotZ28]

Have you changed the fuel filter? How many miles on the car?

[crys36]

Could be the coil pack and module, happened to me.Changed plugs and wires still Ran like crap til it just died 1 day , also make sure your wires are all on the plugs their suppose to be. Its easy to have 2 wires you thought were on the right cylinders until you checked it the 5th time.-Chris

[Loekee75]

In addition to what crys36 and hotz28 said, also check your PCV valve and lines.

[mikelund]

It's a '91. In addition to all of the above, I have changed all the rubber vacuum hoses and connectors on mine. Seems like some elements of the engine systems run better on the correct vacuum pressures. I also replaced the positive cable, not just cleaning, made a substantive difference.