I've been having an issue with my 89. Every now and then, while I'm driving, it'll start running rough. When it first happened, I would just hit the gas accelerator and it would stop and continue running fine. As I said, it wouldn't happen all the time. Then it started doing it more frequently and then wouldn't stop. I'll try my best to describe what it is doing. It almost acts as if it isn't getting enough fuel. It'll shudder and the more I press on the gas, the more it'll shudder. I replaced the fuel filter already and it didn't stop it (thinking it was clogged). I've ordered a new fuel pump, but waiting on that to arrive and install. I'm going to be replacing the plugs and wires this weekend. I haven't done them yet, since I bought the car and it now has 113,000 miles on the vehicle. I'm not sure if the previous owner changed them at some point or not.