Not today, but over the course of the past few weeks, I found a rare way for our I6s to throw misfires. Had a P0305 pop on me 2 weeks ago. Picked up a new ignition coil, got that swapped out in short order, but still had the problem. Figured that meant it had to be the spark plug, so picked up a few of those since they were cheaper, and swapped that in. Rough idle still persisted...
Throwing ideas at the wall, I unplugged the connector, messed with a few other random things, and when I plugged the connector back in, the engine calmed right down. Not understanding what changed, I took the win (for the moment) Engine ran just fine until Tuesday, when on the morning commute to work, the same cylinder went out again.
Long post, not as long as it could be, the issue seems to be the connector itself. I started by jiggling the wires thinking one might be broken inside the insulation, and nothing changed. But when I grabbed the connector and twisted it counter clockwise (not very hard) something in there made enough contact to resolve the misfire. Letting it go, brought the problem back. On a hunch, grabbed my can of electrical contact cleaner and sprayed the socket pretty good, then plugged and unplugged the connector about half a dozen times, before leaving it unplugged so they could dry.
Truck has been running normally for the past 2 days so far. Did take a peek at replacement pigtails, and had no idea they'd be so expensive for what they are. Had been trying to find the model number of just the connector/pins, and go find it on Mouser or something, but with the shipping they charge, I'd be likely spending just as much in the end.
