On the way back from Chicago today, I was about 3 hours into the drive when the car started shaking. It would only shake when throttle was applied. Then I noticed the A/F gauge going nuts. It was then I figured out that I had lost spark to a cylinder. I pulled off at a rest stop and popped the hood looking for anything obvious. I didn't notice anything, I let the car cool for 10 minutes and got back on the road. It was running on all 6 again, but only for about 2 minutes. I drove another half hour until I got to Champaign and i pulled off into a gas station. I added some water to the reservoir and topped it off with gas. Got back on the road and went about 10 minutes until I lost that cylinder again. By the time I got home, the back of the engine was ticking... kinda like a lifter tick or piston slap.

This has never happened to me before and I wonder what would make the car loose spark after a long drive. The engine wasn't overheating and probably never got over 190*. I have a gut feeling that it was a heat related problem though.

yikes.. pull your spark plugs and see if one is Fuel fouled. One should be wet if there is no spark to that cylinder.. is there a bad connection with ur spark plug wire and ur coil pack?

yeah, i would be looking at the absolute basics: ICM, coil pack, plug wire, plug.

pull all plugs, inspect them, mark them, noting any oddities on each, clean them with a soft metal brush(i use brass) and install them in different cylinders than which they came from. then see if you can get it to happen again. if it does, pull all the plugs again and see which one(*) are different than the rest and see if the problem followed the plug or stayed with the cylinder.

if it followed the plug, problem solved, get new plugs. if it stayed at the cylinder, measure the resistance of the plug wires, then swap them to different places(after marking them ), see if it follows.

then to the coilpacks, and if necessary, ICM.

if that doesn't find it in the cheapest way possible, i suck at life.

ALL brand new!

Well, 9 months new... I had a misfire problem that I went the "replace instead of diagnose" route. It was a coil.

Now, do I have to pull the plug right after the misfire happens? I don't know if it'* going to misfire tomorrow, and I'm worried that if there was a wet (fuel fouled) plug, it would be burned off the next time I start the car.

Will a fuel fouled plug look different than the other plugs?

a fuel fouled plug will look burnt and will often have a flakey substance on it.
if a plug is wet it wont be burnt off the next time u start the car if u dont have spark to that cylinder.

You see, that'* just the thing... When I let the car cool, it runs fine! It took 3 hours of driving to get it to misfire.

Is one of ur spark plug wires lying on something hot.. so when the motor heats up it causes ur wire to arc to something metal?

That was the VERY first thing I checked when I popped the hood at the gas station, because that'* what I figured it was. Now there was one plug wire whose rubber ?handle? was sitting on the manifold heat shield. I pulled it off. I also checked as much of the plug wires I could see for white spots where it could be arching. I did this while the engine was running.

The last time I had a plug wire arching out, I grabbed it and it shocked the **** outta me. No shocks today.

I'm thinking more about the spark plugs. I have NGK Iridium tips with the gap set to .030in I think... I wonder if one got too hot or something and the boost was blowing out the spark on a cylinder.

Is this a possibility? Like I said, the entire ignition system is less than a year old.

as stated, it would be best to pull the plugs RIGHT after it happens(well, let the heads cool first, you don't want to dethread them, which can happen with hot aluminum), but if it is bad enough, you may see traces of the issue even after it'* working correctly, but then you might find other issues as well and potentially be diagnosing more than one issue at a time. big no-no.

yes, the plugs, if they are failing to fire, will have what i can bast describe as a flakey black coating around the electrode. that is what you see when running incredibly rich, though lack of spark can cause roughly the same condition if the motor was already up and running. looking for it being soaked with fuel would also suffice.

Ok, I won't drive the car tomorrow until I pull the plugs.

Have I mentioned how much I hate pulling the plugs on the rear, especially since I have a FSTB.