Well that makes total sense then. I would also recommend upgrading to better pushrods like the ones I offer then while you're at it. If you can afford to do it I recommend doing the full AFM delete mechanically on this era of GM v8. These are also certainly a bit more work to work on compared to the previous generation. If you end up paying somebody to do it it will cost you quite the chunk of change.

I haven't in personally experienced it yet but I did see it at the dealership once and have heard of it several times. My guess is this is a newer direct injection engine. It doesn't happen that often but when it does it typically bends the pushrod as well as damaging the lifter. I often tell people if they have a bent to pushrod to make sure that they check the top of the lifter to make sure it's still intact. It can be caused from a couple different things, one could be the pushrod interfering (newer 2014+) and I sell a replacement for that on my website. The other option is that the VLOM is leaking and partially activating the lifter causing it to fail thus causing the pushrod to hammer against it unevenly which eventually damages it. When that happens it's best to install the VLOM plug and a disable AFM in the tune

If the camshaft has any damage it needs to be replaced. This is because once it gets damaged creates a cascading effect were it continues to destroy itself along with the lifter roller.

Pretty sure a lot of mistakes are made on purchases over the holiday break 🤣. Jokes aside though, I'm willing to bet cylinder 7 has a slightly looser tolerance on the lifter bore. This would allow for a little more flow across and around the lifter to go up that oil tower. If the GM factory even made it a half a thou too big it would make a huge difference.

You can't run the tower plugs while you have AFM lifters. When you do this any oil pressure that comes from the main oil galley below the lifters and goes around them ends up pressurizing that tower. That's why when I do the VLOM mod I remove the gasket above the oil tower. This ensures that it can never be pressurized. Now you either have to find a way to remove those plugs or just finish the full delete and replace all the AFM components with non-AFM components.

Ahh, yeah that is a common failure, they usually cause a misfire though. Glad you found it even without the misfire. I do in fact offer aftermarket pushrods for it. They are smaller diameter then factory but use a heavier wall to make them stronger. This is because as it turns out the factory ones don't have enough clearance in some engines to account for wear or machining/casting tolerance changes during assembly. I'm sure the engineers looked at the cad software and said "well, nothing is interfering we should be good" not realizing there was only a few thousands of clearance from the AFM lifter springs and the hole it passes through in the head. So any small amount of wear or shifts that happened during the manufacturing process can cause interference. Here is a direct link to the ones I offer for the direct injection engines. https://www.crazedperformancerepair.com/product-page/pushrod-upgrade Replacing your bent pushrod with the OEM one will lead to you doing it again.

Judging by the fact the rockers are all moving I think you are on the right track I need to get a dial indicator on it. Unfortunately you might have a messed up cam lobe. First though make sure you check for loose rockers on the bottom of all the cam lobes on that side. Just in case you might have a slightly bent push rod or something. Also, you might want to pull the push rods out and see if they are interfering with anything. Check for wear marks on the side of the pushrods. This isn't uncommon because the factory didn't give enough clearance for everyday wear. However, if that's what it was I would doubt it would happen within 20 miles. It would be something that would slowly get worse and worse over time.

From the description on the invoice I would say there is a good chance the lifter release trick could work for you. You need to do your part though and verify a sloppy loose rocker on cylinder 7. It is the rear most cylinder on the driver side. Do you have any mechanical skills or know anyone close to you who does? This is the type of job that even a novice and some completely inexperienced, can accomplish with the guidance from my video. I do have to note though that it's not a guarantee that the truck will be successful but your odds are good. Also not that the more you drive it like that, the lower your odds of success

I'm definitely not close enough over in SD. It is expensive to do a full delete considering hrs taken to do one. I typically charge about $4400 out the door with all things including. I do the oil pan and sump o-ring, machine heads, new timing components the hole ordeal. I also usually find other things needed as well since I inspect vehicles while in shop. I typically notice leaky oil/trans cooler lines, loose suspension parts and dirty driveline fluids. If the cooler lines are leaking it's a no brainer to do, since the oil pan is out of the way I cut that labor in half. The rest just comes as a courtesy in hopes I can upsell more work. Then after I'm done I show all the bad parts to the customer before they go in the scrap bin. Apologies for the delay, it's been crazy lately, maybe a day or two after I messaged you I had a cutoff wheel explode into my hand. Almost all healed up now though so things are going better.

When these lifters fail they don't come and go so to speak. They typically fail or they don't. The failure is always caused from lack of oil pressure during activation unless it is spun in the bore from a bad plastic guide. If the afm disabler isn't working then most likely you have something else going on. I am a very straightforward person and with that said I will give you my opinion on the shop. Looking at it from your side of the story, the first time the shop looked at it they didn't know what they were getting into. So not no one what they were getting into they just assumed bad engine and told you that you needed to replace it. It most likely didn't need an engine. If they told you 4 years ago a delete was $2k and now it's $5k they aren't being honest with you. The parts have only increased in cost about 15% 4 years ago a delete kit was $600-700 and now it's $700-800 for parts. Expecting they mark it up the usual mark up it should have went from $1000ish to $1200ish. The labor hrs hasn't changed. It takes 20-25hrs depending on if the oil pan is getting pulled or not. So at $100per hr (for example) do the math. Then you have the tune to shut off AFM. That's $50 from lt1swap.com and hasn't changed. The other cost would be machine work to the head. So unless the went from $40 per hr to $120 per hr it doesn't add up. Where are you located? Perhaps I know someone or am close enough myself. You really should get it actually properly diagnosed.

Sorry for the long delay, I'm forgetting to check the forum and my phone doesn't notify me properly. Anyway if you haven't solved the issue by now it sounds like you might have a issue at cold start. Check for codes and see what codes you have. If you post the codes hopefully this time I will catch it soon enough to actually help you diagnose it. You could also shoot me a message just to get my attention. I do get notified of messages better than I do forum post.

https://amzn.to/44MHP6d

Awesome, thanks for posting. The cleanliness on those connectors can be critical. If there's a small grit of sand preventing it from fully seating down it will have a poor connection. Thanks again for confirming and bringing this post to everyone's attention?

Yes this will solve your issue. The VLOM is typically the source of failure for the LT based direct injection engines. See https://youtu.be/efV9q5k-3SM for reference.

Yes the tune is needed to fix the activation attempt's. The lean codes might or might not be related. You should just get the two and done first in order to see if the problem comes back or not for the lean codes. I recommend LT1swap.com for the tune.

So this is strange, I have a program where I can take codes and look into the common failures for them. All the codes you give don't give me any common failures except for the map sensor code p0107. Hi attached a screenshot from my phone of what the common failures are for it. I don't think it's going to be very helpful though. Out of curiosity have you reached out to LT1swap.com to see if something may have happened when the tune was done? Perhaps a file corrupted or something during the upload.

Just for good measure until I dig up diagrams myself and look into it. Can you measure voltage between driver head and where the ground strap meets the firewall stud with the key in run position? I've seen the strap get corroded to the point of failure since it's a non insulated braided wire. You should see zero volts if the wire is good.

You mention having and clearing codes but never gave the codes. Those codes are critical to diagnosing remotely. What was the codes you have? Edit: I see that you added the codes to your original post and some more information. I will dig into this some and see what I come up with at some point today. Sorry it took so long to reply I got distracted and forgot about the post until I checked my notifications.

I would be very cautious with this. There's a good chance you will end up with a collapsed lifter again by running the AFM at all. It's a much better option to do the tune because it will still pass emissions. As a side note: if you choose to risk leaving the system available for the sake of emissions test, pay very close attention to your oil pressure. If at any point at all it drops below 26 PSI while it activates(it's most vulnerable while it comes to a stop sign), it will bind and damage the locks in the lifter. This is the reason for lifter collapse in the first place. Unfortunately that is for 26 PSI at the lifter, the oil pressure sensor does not measure the pressure at the lifter. It only measures the pressure before it goes to the solenoids for the lifters. So if your VLOM gasket leaks or solenoids don't flow correctly It will be below that 26 psi and you won't even know it. You will just suddenly have a collapse lifter at some point. With all that said though I'm glad you got it taken care of and working.

You might want to pull a wiring diagram and follow that wire you grounded to see where it's supposed to ground to. I'm too busy now to look it up. Remind me later if you need me to pull one. I'm open to do it on here because it's a gm AFM related post. Normally that's reserved for the premium membership forum area. One big thing to consider though is that it might not be a wiring issue at all. What other codes do you have? It's possible that the computer is seen something that makes it not want to ground the coils. It's perhaps disabling it has a safety thing to prevent damage.