I picked up AC Delcos from Advance/Checkers. Price was right and the first set lasted 130K.. Can't complain about that quality level.

Autolite platinum AP605, is there a better option ?

NGK Tr55'* work well
Delco Iridiums work well
Those plats work well...

All good stuff.

Will be getting new wires sometime this week, just gotta find some time to put em on. I'm a college student so that takes up most of my time. Yesterday I discovered that i could get my check engine light to go off by getting up to at least 70mph. Once I got back into town and drove around a little it sounded better although the misfire was still apparent. But when the light is on it sounds much worse. Eventually the light comes back on, but often takes alot of driving around to register. Also what is the correct way to test the primary windings on the ignition coils ? I've read the techinfo article and used pieces of wire, but i got all zeros for the primaries on two of the coils. Does this mean at least one is or could be bad? The secondaries all came out around 6,000 ohms.

Our cars use 3 coil packs . They spark 2 cyl at same time one spark is wasted at the exhaust stroke. #3 at comp and #6 at exhaust.

You plug 6 into 3 and 3 into 6 and see which cyl misfires now (It only matters that cyls are plugged into the corresponding coil pack not terminal .) either terminal on the coil pack will work.. If you do this and now #6 misfires you have a coil problem.

If 3 still misfires with the wires switched, the coil is most likely good since it fired #6 fine ( #3 coil output is now firing #6 cyl fine). and you now have 3 plugged into a known good coil output because #6 worked correctly . Iit could be #3 wire, spark plug, or fuel inj., or fuel inj signal.

If cyl 3 still misses swap #3 fuel inj with the one next to it and see if problem stays at #3 or follws that inj .

Just my 2 cents. I assume a certain skill level . [/b]DO NOT ATTEMPT FUEL INJ SWAP UNLESS YOU KNOW HOW TO RELEIVE FUEL PRESSURE AND WORK SAFELY

still having troubles. Did the plugs and wires yesterday, seemed to help a bit. Car still shakes at idle. There is definitley spark. Could it be fuel related? I'm going to check the O2 sensor next.

personally it sounds like a fuel injector i have seen mainy injectors fail mainly on gm 3100 sfi but run a can of sea-foam through the system and that should solve the problem it is alot cheaper to clean injectors then buy new ones due to the cost

Not too sure on the injector. While POSSIBLE, it'* extremely rare. 90 percent of the time, it'* ignition related in some manner. Typicall plugs/wires/coils. Aside from that, tighten your ICM bolts to the bracket. Those are critical grounds.

Swap coils around as suggested to see if the misfire moves. Measure your coils per Techinfo.

Measure the resistance of each plug wire.

If your misfires are RANDOM, be looking carefully at your alternator output. That can have a big effect on spark voltage. Power and grounds for multiples, individual components for cylinder isolated misfires.

Could be injector. however I'm running with Wren on this one.

Check the coil pack bolts, and ICM connector bolt. If you still think you have a problem, let me know if you want to swap your ICM with a test one to see if it'* a problem.

I think i can rule out the injector, forgot to mention I replaced # 3 with a new one a while back. The o-ring was bad though, the other ones might be worn as well. When idleing my rpms drop to under 1000 and i can feel the car stumble. Also the coils came up with the right voltage when I tested them so i dont see them being a problem.