Recently had issues with my coil pack and decided to pull plugs to clean and check. All seemed fine, gaps were pretty damn good, uneven wear but no fouling. The resistance after cleaning measured around 5800 ohms on 2, 6600 on 3, and one was at 7400. They're the standard replacement AGSF24FM. Anyone know where to find resistance specs? Cannot for the life of me find anything.

Additional questions: My coil pack issue started with a cyl 2 primary/secondary OBD code and was blowing the "Engine #2" (which does *not* mean cyl 2) fuse within 20 seconds of starting up. This only seemed to happen in the cold, below 20 degrees or so, closer to 30 would start okay. My dumb *** eventually replaced the 15A fuse with a 20A to get the engine to just warm up, then restarted with a 15A. Ran fine for a few minutes, but ended up blowing cyl 3 and 4 on the coil pack. So... Was my coil pack fine and it was just the 7400 ohm plug blowing the fuse in the cold, or was my coil pack itself starting to go and caused the wide variety of resistances in the plugs over time, or maybe the 20A fuse screwed the plugs resistance? Also, what in the hell is "Engine #2" fuse for exactly? Couldn't find any info on that at all. It's Fuse 40 on the diagram.

Thanks guys, appreciate any tips.

 

Edit: I'm an idiot x2, was using the wrong reference for acceptable resistance levels so it looks like my current plugs are fine. Would still like to know where to find that info though, and what the "Engine #2" fuse (40) is for.

 

Edit/rewrite: Had replaced engine ground strap and coil pack, that fixed all errors until a brief high RPM run to clean the engine which killed cyl 3 & 4 on the coil pack again. Exchanged alternator in case it was overcharging, put in new coil pack, and have been fine except once or twice got TPS errors and failsafe mode again, plus fuse 40 blew once as well but coil pack is fine. Haven't had any issues for a few weeks, cannot tell if moisture or heat play a factor or if it's just a sporadic electrical issue with the PCM or wiring.

To anyone experiencing similar issues, before replacing parts, I recommend: Test battery and alternator, disassemble battery clamps and clean the wires and clamps, and put all new ground straps in (cheap & easy & very important). Problems beyond that are likely wiring, so inspect any areas where your harness might rub against anything or shake a lot. If that comes up clean, it's probably just an aged and glitching PCM. If you're just getting TPS errors and all of the above don't solve it, get a cheap generic TPS off amazon or ebay, they work perfectly fine and will be a cost effective way to diagnose whether that's actually the issue.

Keywords/details for people searching:
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Fuse 40 engine #2 coil pack cylinder 2 B

 

Thanks for posting the problem and solution! I'm sure someone in the future will appreciate it.

To anyone that posts questions to this thread in 2+ years, you probably won't get an answer back because...it's been 2+ years! I'd suggesting stating a new thread at that point.