My 1992 naturally aspirated started missing and studdering under load while at lower RPMS, and now it even backfires sometimes. Its got about 200K miles on it. My SES light has not come on.

I've tapped the MAF while idleing, that doesn't do anything. Its been probably 25K miles since I did plugs and wires, could that be the problem?

I've read about tons of problems with the coil packs on this message board, I'm guessing it could be that, too?

Thanks,
-Ryan

Have you looked over the wires to make sure non are rubbing or grounding out?
What brands of plugs and wires are in your car?

Yes I've inspected the portions of the wires I can see, they all look good and the routing looks correct. I've pushed them around with a piece of wood while the car was idling and I didn't hear any change.

The wires are whatever the cheap brand was at the parts store, the plugs are AC Delco.

The car has always had a little bit of a rough idle, that i could never get to go away with Sea Foam, new O2 sensors, plugs + wires, etc. So I wonder if my coil pack has always been a little bad. I've tested the resistance before and it was OK though.

I just looked on O'Reilly Auto Parts' website, I can get an AC Delco coil pack for $46 bucks. Seems pretty cheap, I'm not sure if its refurb or not. It says "DELCO REMY" in the description, I don't know if that means remanufactured or what. I'm thinking about going and picking that up, I think they are pretty easy to put in?

Also when I had it in the shop for an oil change a few weeks ago they said my vacuum lines were looking bad and may need replaced soon. Could that be it?

Anyone want to weigh in? I was going to buy some parts on my way home tonight, don't know if I should start with plugs + wires or a coil pack. The coil pack is a lot easier to put in, and is less expensive if I go with AC Delco wires.

If you got the "cheap" plugs, they could be worn. Put in some good plugs (stay away from Bosch) and correct the vacuum leaks. See if that improves things.

A new set of plug wires cleared the problem right up. Thanks for the help.