s14 ignition coil? Loss of power, sputtering, etc

[invain]

Been having some problems with the ka-t again and I've got it narrowed down to ignition. The problem has been very intermittent, which doesn't help matters because everytime I try to check things out the car runs fine.

What I'm getting is bad stuttering/loss of power through pretty much all rpm's. When I take off from a stop the car almost falls on its face and I can tell I'm losing a ton of power, just drives like absoulute **** and bucks half the time. Sometimes one cylinder will stop firing completely, and although the sputtering stops of course it drives like ****. The strange thing is, it does this randomly. I drove the car 110 miles from home to college and it was perfect the whole trip. 3 days later I'll drive 10 minutes to get groceries and it's drives like ***. A week later I hope in and it's driving normally again.

I pulled into a rest stop one day when the car was acting up and found cylinder number 2 was not firing. I was pretty sure this was electrical since the problem appears randomly so I started with the cheapest fix and got some new spark plugs. Just put the new plugs in today and it does drive a teeny bit better, but half way back to my apartment it starts acting up again and is sputtering/losing power like mad. Half an hour later I leave for a football game and the car drives like a dream there and back.

Obviously it wasn't bad plugs, so now I'm thinking ignition coil? I haven't taken the distributor cap off yet to check that out but the original owner of the car had recently replaced the distributor and wires so I don't think it's either of those two.

I tried checking in the FSM but I still don't know where the ignition coil is. Any of you guys have any diagrams/pictures? If I replace the coil, should I just get an oem one or would an aftermarket one make any difference?

If it helps any I'm running about 8 psi and the car has cams as well.

[xweav32]

have you changed plug wires?what is you timing at?are you sure its not a fuel issue?

[invain]

I've thought about fuel, but I ran some dry gas and fuel cleaner through it and didn't seem to make a difference. If it were fuel I don't know why it'd be so random either. I am gonna change the fuel filter next time I'm home however. No clue about timing, have never messed with that.

[xweav32]

what about maf? and cel's?

[invain]

Maf should be fine, I cleaned it a while ago and haven't had any problems with it. Not sure if the problem would happen randomly like this if the maf were involved either.

No cel's. I've pulled codes twice now and got nothing each time.

[xweav32]

what a plug wires? and cap/rotor?

[invain]

I'm gonna check the cap/rotor at home next weekend. Wires are all pretty new.

[xweav32]

cool let me know wat u find

[asoomal]

Pull out the ECU and try to see fi you get any codes. (Not all problems will trigger the CEL.)

[invain]

I have pulled the ecu and checked for codes, twice.

Still not sure where the ignition coil is, anybody got a pic? I feel like the problem occurs more often than not when the car is good and warm, which would make sense if it were the coil going out.

[Deny Reptile]

Sorry to bump an old post and I don't know if you ever found it, but this is for anyone trying to trouble shoot this as well. The ignition coil is located with the distributer, if the coil is bad then its best to replace the entire assembly. I fund this out in one of those Chilton books they sell at o'reillys and autozone.