SeedyROM

I have the worst timing with this Max and I'm hoping I haven't just lost a cylinder. Anyway, here's what's led me to the video below.

1) Month ago, car stumbling and running on five cylinders. Replace single ignition coil (unsure which), all is fine.
2) Last week, occasional single misfire at stop lights. First 1 in 10 stops, then 1 in 5, then every other stop. Also hearing a strange rattle when letting off the gas. Mechanic diagnoses bad rear precat for rattle, misfire not happening when I take it in (of course). Rattle comes and goes, power/acceleration is fine.
3) Today: Driving it sparingly all week while waiting for precat but tonight started stumbling again like the ignition coil is bad. Now I've got a louder noise/rattle and I get my first: P0301 (Cylinder #1 misfire).

I drove it the 10 miles home as it would only stumble/rattle at low speeds. Before driving back, it sounded a bit like a lifter but was inconsistent on RPM. When video was taken 10 miles later, seems more consistent on RPM up to 2k but flutters on letting off gas. I guess I'm going to find out tomorrow but I'm debating whether or not to drive it the 20 miles into the shop tomorrow...thoughts?

Video, second half is much louder/clearer.

Thanks in advance!

samtr87

Rod knock?

SeedyROM

Oh man I hope not. Two Nissans in a row if that's the case but the fluttering nature of it on the trailing end does seem to support it. If it was in perfect rhythm with RPM it'd be more likely lifter or something else...

SeedyROM

Well I'm going to start it up this morning and see how it sounds. If the same, I'll tow it and if not, I'll try to limp it there. I'll report back if we figure it out.

SeedyROM

Good news! Reporting back in case anyone else has a similar issue.

Apparently that loud knock/rattle was actually my rear pre-cat which I was going in to replace anyway. The center section had detached from the outer pipe and was banging against the shell along with the RPM, causing what sounded like a nasty engine problem or rod knock. Once the cat was changed and ignition coil #1, the car came right back to life and was quiet. We're going to pull the plenum and change all the plugs and coil #3/5 (since they are impossible to get to otherwise) just for good measure and I'll pick it back up tomorrow.

Thanks guys.