[Endlessblockades]

I'm going to do a wire/plug/pack inspection tomorrow, but after reading a bunch of threads, I'm hoping I have an injector problem. I'm positive they are the original units. Runs fine from cold start, stumbles on a warm start. I watched Timmy and Sean's video and YOLO'd on a full set of the Denso reman injectors, fuel rail crush washers, and gaskets from MotorWest Performance. Not even sure that's the problem but that's how I roll, unfortunately. Doing one is enough of a PITA so, why not? I will move the coil pack but I doubt that's it. CEL is on but not flashing so I can limp it around to stay ahead of the streetsweepers, right?

[mtbtim]

Like you mentioned, your first step should definitely be to swap the coil packs. Swap the #1 and #3 coil packs and see if the misfire moves to the #3 cylinder. This will confirm or rule out a coil pack problem.

If the misfire stays at the #1 cylinder, you can pull the spark plug and take a look. If the electrode looks worn, you may as well replace all 6 spark plugs because they are due. While you have the spark plugs out, this would be the opportune time to do a compression test to check the health of all your cylinders. Sean and I have a video for that as well.

If the new spark plug does nothing, then I'd look into replacing the fuel injectors using our video.

Good luck!

[Endlessblockades]

Originally Posted by mtbtim

Like you mentioned, your first step should definitely be to swap the coil packs. Swap the #1 and #3 coil packs and see if the misfire moves to the #3 cylinder. This will confirm or rule out a coil pack problem.

If the misfire stays at the #1 cylinder, you can pull the spark plug and take a look. If the electrode looks worn, you may as well replace all 6 spark plugs because they are due. While you have the spark plugs out, this would be the opportune time to do a compression test to check the health of all your cylinders. Sean and I have a video for that as well.

If the new spark plug does nothing, then I'd look into replacing the fuel injectors using our video.

Good luck!

Thank you - that is exactly my plan! I went ahead on the injector set while secretly hoping I don't need then (yet). Do you happen to know why a hot vs cold engine affects the misfire? I have barely driven 3 blocks since the misfire began, but is seems to only happen on a warm restart. Thank you guys for your support and videos.

[alumarine]

Originally Posted by Endlessblockades

Thank you - that is exactly my plan! I went ahead on the injector set while secretly hoping I don't need then (yet). Do you happen to know why a hot vs cold engine affects the misfire? I have barely driven 3 blocks since the misfire began, but is seems to only happen on a warm restart. Thank you guys for your support and videos.

A bad coil might only act up when it's hot.
Could be other things as well.

[Endlessblockades]

Originally Posted by alumarine

A bad coil might only act up when it's hot.
Could be other things as well.

It's the other things that worry me - but, onward......

[Endlessblockades]

So given the lack of time yesterday I got as far as swapping coil pack in cylinder 1 with 5 (meant to do #3 but a nasty cold / brain fog is my excuse - first one since well pre-covid). I didn't realize I didn't have a 5/8 socket, so I couldn't pull the #1 plug. The reason I'm even mentioning this half-assed progress it to mention that the seat for the #4 cylinder (on the #1 coil pack) was full of crusty dust and the metal pin was encrusted with turqouise, uh oxidation?. The other 2 on the passenger side did not have that. Unfortunately, I cleaned and blew it out for the most part before I took the photos below, so keep in mind it was way worse looking than the other two. The #4 cylinder didn't seem affected, but I am wondering if that may point to an issue with the coil pack that was sitting on #1 or some resistance somewhere else?. Hoping the misfire issue moves to #5 or #2. While I was moving the intake out of the way I did clean the MAF - the wire was filthy. I cleaned it last a couple of years ago..... thanks for any insight. Will check plugs next before investing in a compression test kit.

P.S. I'm using an OEM air filter but have been to the desert several times.

[Endlessblockades]

After swapping packs, I now get a PC of 0300. Should I wait until it goes full TC/CEL (will it ever pinpoint a cylinder?), or is the new Random Misfire code enough to lean towards coil packs? I got the new code within less that a mile of driving after a couple warm starts. Give it some more time to collect data? God I hope it's just a coil pack. I need to go camping at a bike race in less than 2 weeks.

If it turns out to be that, I will do 6 plugs since I'll have the slightly more involved side exposed anyway. Am I being too hopeful here without further testing?

[phattyduck]

Originally Posted by Endlessblockades

. While I was moving the intake out of the way I did clean the MAF - the wire was filthy. I cleaned it last a couple of years ago.....

The picture you show there is just of the temperature sensor. If that's dirty, it doesn't matter much. The wire that matters is down inside the venturi tube.

-Charlie

[Endlessblockades]

Originally Posted by phattyduck

The picture you show there is just of the temperature sensor. If that's dirty, it doesn't matter much. The wire that matters is down inside the venturi tube.

-Charlie

Yes, I drenched the innards with MAF cleaner as well. I didn't realize the exposed wire was only for temp, though - thank you.

[Endlessblockades]

Update. New coil packs and wires has it running beautifully. I'll shelve the injectors for the distant future...