Misfire & Carbon deposit help

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Molon Labe
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Just a dumb possibility .....is it possible the #1 cyl is one of the cylenders that shuts down on the hiway , when under little load is detected???
i have the AFM disabler unit (range)

& as already answered yes cyl#1 is a AFM cylinder
 
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Doubeleive

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i have the AFM disabler unit (range)

& as already answered yes cyl#1 is a AFM cylinder
time to invest in a scanner.
I drove the wifes rig today for the first time since they did the injectors to take it to get a smog inspection, it drives a lot better now than it did, passed smog test no problem.
 
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time to invest in a scanner.
I drove the wifes rig today for the first time since they did the injectors to take it to get a smog inspection, it drives a lot better now than it did, passed smog test no problem.

Yeah. i mean i have a scanner which is where i got the fuel trims from earlier but it’s not throwing any codes other than cyl 1 misfire and a weird “cold start rough idle” code or something off the wall it only set once and won’t set anymore.

MAP , MAF, etc. seems like it’s where it’s supposed to be and everything else seems to check out afaik. Any other data points on the live data i should be looking for ?
 

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Yeah. i mean i have a scanner which is where i got the fuel trims from earlier but it’s not throwing any codes other than cyl 1 misfire and a weird “cold start rough idle” code or something off the wall it only set once and won’t set anymore.

MAP , MAF, etc. seems like it’s where it’s supposed to be and everything else seems to check out afaik. Any other data points on the live data i should be looking for ?
That cold start misfire/rough idle is what was wrong with the wifes truck
I made a video of what I found, basically I was checking the misfire counts and looking to see if the injector was being shut off or not
seeing what the fuel pressure was etc,
did you try swapping coils plugs around at all yet?

 
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AGo1cEF.jpg
 
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that was #3 what about the rest, thought you were having a cyl 1 misfire?
That was #1.

P0301 cyl 1 misfire. I swapped plugs and coils around no change. I replaced fuel injector cyl#1 with GM genuine and fuel trim came out of the negative but, noise persisted (even sounded worse almost) . Pulled valve cover, see result
 

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That was #1.

P0301 cyl 1 misfire. I swapped plugs and coils around no change. I replaced fuel injector cyl#1 with GM genuine and fuel trim came out of the negative but, noise persisted (even sounded worse almost) . Pulled valve cover, see result
if you are really really lucky you might be able to get it unstuck and throw some snake oil in it and see what happens
 

hatinthering

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That was #1.

P0301 cyl 1 misfire. I swapped plugs and coils around no change. I replaced fuel injector cyl#1 with GM genuine and fuel trim came out of the negative but, noise persisted (even sounded worse almost) . Pulled valve cover, see result
That was the same cyl/valve that failed on mine in thread below..."P0301 and 0300 codes."
The repair ain't fun, but do-able in the home garage if you're inclined.
 

JJ1971

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I am in the process of putting mine back together deleted. Mine #4 intake valve was like your video. Had misfire code for #4. The lifter came out in three pieces and the pushrod was bent. Also pulled a bent pushrod out of #1 exhaust valve. Had no misfire codes for number 1. Melted converters. All plugs but number 4 looked like yours. I assume it kept spaying fuel. Engine would not even run until the converters were unbolted. I suggest a compression test on all cylinders or pull the other valve cover.
 
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I am in the process of putting mine back together deleted. Mine #4 intake valve was like your video. Had misfire code for #4. The lifter came out in three pieces and the pushrod was bent. Also pulled a bent pushrod out of #1 exhaust valve. Had no misfire codes for number 1. Melted converters. All plugs but number 4 looked like yours. I assume it kept spaying fuel. Engine would not even run until the converters were unbolted. I suggest a compression test on all cylinders or pull the other valve cover.
Sorry to hear.

i am at a crossroads with what my next step is going to be. heart is broken lol.
 

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You are half way there. You know what the problem is and you have the valve cover off. Pull that head, replace the lifters on that side, check for bent push rods, get the head decked, and reassemble.
I am not minimizing the work, but still…
 
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You are half way there. You know what the problem is and you have the valve cover off. Pull that head, replace the lifters on that side, check for bent push rods, get the head decked, and reassemble.
I am not minimizing the work, but still…
True true but it’s more of a mental battle for several reasons including probability. This truck has already proven unreliability in less than 6k miles, one issue that drove me mad (door locks unlocking), & two catastrophic failures. If i fix , what’s next .. if i did the repair and then 2 months later the trans goes out idk what i would do lol

then there is also the fact that i literally see no point in doing the repair without doing the afm delete. If i do the delete now we’re talking about a job.

love the truck and i have no doubts that i could do the work myself. But do i have the time, patience, or mental fortitude at this point is still to be determined.
 

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True true but it’s more of a mental battle for several reasons including probability. This truck has already proven unreliability in less than 6k miles, one issue that drove me mad (door locks unlocking), & two catastrophic failures. If i fix , what’s next .. if i did the repair and then 2 months later the trans goes out idk what i would do lol

then there is also the fact that i literally see no point in doing the repair without doing the afm delete. If i do the delete now we’re talking about a job.

love the truck and i have no doubts that i could do the work myself. But do i have the time, patience, or mental fortitude at this point is still to be determined.
Understood, and only you can make that call. I had to do mine THREE TIMES because I got a set of bad aftermarket lifter trays with the first cam I bought that let the new non-AFM lifters twist in their bores and take out two cams. But would I do it again? Absolutely - especially now that I know what to do, and not do. We'll be here if you decide to take it on. We like DIY types around here. :)

And while these trucks do go through phases of needing repairs, they are ultimately very reliable and long-lasting trucks. And once you know your way around it, keeping it reliable for many, many more years is entirely doable. I'd drive any of ours anywhere without a second thought.
 
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Understood, and only you can make that call. I had to do mine THREE TIMES because I got a set of bad aftermarket lifter trays with the first cam I bought that let the new non-AFM lifters twist in their bores and take out two cams. But would I do it again? Absolutely - especially now that I know what to do, and not do. We'll be here if you decide to take it on. We like DIY types around here. :)

And while these trucks do go through phases of needing repairs, they are ultimately very reliable and long-lasting trucks. And once you know your way around it, keeping it reliable for many, many more years is entirely doable. I'd drive any of ours anywhere without a second thought.
But wait, isn’t your truck an 2500/3500 ? Certainly that truck is on a more reliable & long lasting level than the quarter ton models. either way, i do appreciate the encouragement, lol. If i decide to do i will definitely be asking the forum some questions .. so i appreciate TYF for always trying to help out.

i know everyone here is like cmon man just rebuild it what’s the problem.. if you haven’t been following the [very short] journey I’ve had with this truck you would probably need context. Like i haven’t really even had time to bond with this truck other than under the hood fixing shit :rolleyes: Like i know that is bonding in a way but lol.. if i wanted to do a frame off restoration it would probably be a 73 caprice 2 door with a 454 big block.. not my DD

Not trying to ***** , just frustrated.

I just checked and the afm delete kit they had on rock auto is now sold out, something told me to buy it when i saw it like a month ago but, i couldn’t justify spending like 500 bucks on parts for a project I definitely did not foresee myself doing any time soon.
 

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But wait, isn’t your truck an 2500/3500 ? Certainly that truck is on a more reliable & long lasting level than the quarter ton models. either way, i do appreciate the encouragement, lol. If i decide to do i will definitely be asking the forum some questions .. so i appreciate TYF for always trying to help out.

i know everyone here is like cmon man just rebuild it what’s the problem.. if you haven’t been following the [very short] journey I’ve had with this truck you would probably need context. Like i haven’t really even had time to bond with this truck other than under the hood fixing shit :rolleyes: Like i know that is bonding in a way but lol.. if i wanted to do a frame off restoration it would probably be a 73 caprice 2 door with a 454 big block.. not my DD

Not trying to ***** , just frustrated.

I just checked and the afm delete kit they had on rock auto is now sold out, something told me to buy it when i saw it like a month ago but, i couldn’t justify spending like 500 bucks on parts for a project I definitely did not foresee myself doing any time soon.
Ah, sorry - my bad. The AFM delete was on my 2012. It was a whole saga that this group helped me manage through. Lots of helpful perspective from experienced people at key points was a Godsend. It's one of the main reasons I stick around - to help other people where I can. If you lived nearby, I'd set aside a weekend and do it with you over some beers.

And I totally get the frustration. Both my '12 and '07 needed attention when I first got them. I bought my '12 with 92K on it and it gave me the low oil pressure warning on my first trip with it, which was through the mountains of Colorado in a snowstorm. I bought my '07 with 196K and it needed front suspension work, motor mounts, and a bunch of other things. But I still have both because they're now so reliable it would be silly for me to get rid of either one, as long as I can still afford the insurance and personal property tax each year.

My main point is that once you get through the crap the PO ignored or deferred, and the AFM crap, these can be extremely durable and reliable trucks over the long haul. And most of all, having done so much work on them over the years, gives me confidence that I can handle anything that comes up. That's great peace of mind when I'm 2,000 miles from home, and 150 miles from a service station with my wife and kids.
 

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