I was driving yesterday and felt the car stumble and buck a few times with no clear pattern to it. It did this for maybe 15 minutes then ran fine the rest of the way home. It wasn't a steady constant misfire, just every 10-20 seconds or so it would sputter and buck, then run normal. The car also did the the very first day I had it, on that day it was misfiring so bad, black smoke was coming out of the tailpipe and it stalled just once. The CEL never lit up on either ocasion. Other than this completely random misfire problem, the car runs great. Always starts right up quickly even when it's -5 Fahrenheit outside and has averaged 38 mpg over the last 5 tankfuls. The car has new (non-OEM) plugs and wires. I am thinking that the ignition coil is flaking out on me. What do you think? Coil or something else?

 

How old are the distributor cap and rotor?

 

Not too sure.

 

Inspect them for wear and corrosion. They should be the first thing you check. Also inspect the new plugs while you are at it.

 

i would also check the timing but its more than likely an issue with fuel or spark. check the cap and rotor for corrosion build up and also change the fuel filter if its not been changed in a while.

 

Well, ignition timing, which is also a possibility of being the source of the problem, has to do with spark.