I hope this is in the right section. I wish I had a turbo with an anti lag setup pushing tons of power, but I instead have a pretty stock ap1 with 70k miles that is misfiring. When the engine is cold, it misfires below 3k. Light throttle over 4k when cold is pretty smooth. However, more then quarter throttle above 4k results in misfire. Damn, thing sounds like a boxer motor. When warm, idle to 3k misfires, but 3k on is pretty smooth. First scan was p0301, p0303, p0300, p1399, and 61-1. Since then I have cleaned the IACV, new NGK plugs, switched coil #1 with #2, #3 with #4. Disconnected battery overnight and then drove it a bit til it threw codes again. This time p1399 and 61-1. I'm stumped. Which route should I choose? Coils, valve adjustment, or injectors? Any insight would be very helpful.

 

See here: https://www.s2ki.com/forums/s2000-un...thread-378792/

"First scan was p0301, p0303, p0300, p1399:"
And then you switched coil packs "#1 with #2, #3 with #4":
To be honest, your codes don't make sense to me after you switched the coil packs -- they seem incomplete. Can you scan again?

Also, how much did you torque your spark plugs? Should be ~21 ft-lb.

 

In this order:
1. Make sure sparks are torqued correctly
2. Check/adjust your valves
3. Replace coil packs (hopefully with a local member first, but I'd just shotgun it at this point personally...I doubt they're all bad)
4. Compression check

 

Thanks for the response! I scanned again and its showed misfires on all 4 cylinders. I torqued plugs to 24 ft-lb... maybe a little too much on my part.

 

I'm adjusting the valves tomorrow if I have some time, and I think I can get a couple coil packs from someone locally to check on those after the valve adjustment. Thanks for your insight. It's very helpful having you guys while I go through choices in my head on what to do next.

 

If you're in Arizona I can lend you three known good OEM coils and four known good fuel injectors to test with.

 

Thanks for the offer! Might kill my catalytic converter misfiring all the way to AZ from Central California though. I appreciate the help! CenCal people... where you at?!?!

 

Valves adjusted at dealer and he tells me the mechanic thinks its burn valves. It's still misfiring so I start freaking out thinking $$$. On the way home I picked up a loaner compression gauge, and thankfully it showed 210 across all cylinders. At this point I was tired of being stressed out so I got 4 new coils and she's running fine now! I'm glad I didn't have to move to the next step with injectors. Thanks for the help guys!

 

Very interesting that all of your coils gave up. Good stuff man, glad you got it solved!

 

Actually, I'm sure two of them are fine. I just bit the bullet and got all 4 just for piece of mind that I'm not going to have to do this again any time soon. And now I may have 2 good coils as spares! Also my OBD2 reader should be arriving at my doorstep pretty soon. I was driving a couple blocks to O'rileys just to get my codes. All in all, I'm really glad it didn't require any head work or injectors. I'll take this as a learning experience.