Sufarry

See ya there lol! I guess now that it runs right I have to actually care about it, so i gave it it's first bath in a LONG time lol.

Thank you! Yes I am definitely feeling the high! With as much time, energy and money I've put into this thing, it better be problem free for a while 🤣. I will say, I was doing a quick inspection while I had the pan off and the crank, rods and cam look brand new still at 200k miles! No oil buildup, etc! The cam lobes looked perfect too!

PROBLEM SOLVED: LINK TO VIDEO Well guys, I did some digging in the oil pan today and found the missing bolt. I pulled all of the tone ring bolts out, threw some blue loctite on them and buttoned everything back up. Sure enough the knock is gone! It sounds like a normal 24v again! FINALLY! I've been chasing this issue since 2021! Thank you to everyone who offered advice or suggestions! I'm so thrilled I get to close this chapter. I hope if anyone else has similar symptoms in the future that they find this post and can solve their issue and not spend near as much time and money as I have going through this truck.

HUGE MEGA ULTRA UPDATE: LINK TO VIDEO I have finally found the issue, I think! I had time today to pull the pan off (btw, this can be done on a 2WD without removing the engine, maybe I'll do a write up on it). After removing the pan, I turned the engine over by hand to visually inspect the crankshaft tone ring. Now, I should say that I inspected this ring before but only with an inspection camera through the sensor hole and did not see any issues. The sensor also is not damaged or nicked in anyway to indicate any issues with the ring. The tone ring is a 2 piece ring. There are 5 bolts that hold the ring in place. 3 bolts on the large piece and 2 on the smaller piece of the ring. Well, one of the bolts on the smaller ring has backed out completely and is missing. The other remaining bolt on the smaller ring is bent. I can literally move more than half of the tone ring by hand! You would think that a ring this loose would cause a CEL for CAM/CRANK correlation codes or something, but I guess not. It must be just off enough to cause a wild timing scatter but just on enough to be within "spec" of the CEL condition. I ordered a new (used but in good shape) tone ring and all 5 bolts. I'm going to remove my ring this weekend and install the new one and LOCTITE THE CRAP out of the new bolts. I will post a follow up update the moment I get the truck running! FINGERS CROSSED THIS FIXES MY ISSUE!

UPDATE: I found, in the depths of another forum, someone with the same exact issue as me. Here is a LINK to their video they posted 16 years ago! They went down the same exact rabbit hole I did and ultimately ended up pulling the oil pan to find a damaged tone ring. I inspected my tone ring through the CKP sensor hole but its a very small area and I wasn't able to really good a good look at it. I'm going to pull the oil pan tomorrow and give it a real inspection. I HOPE I find an issue with the tone ring so that I can finally put this to rest!

📸 How to Enter:Post ONE photo of your truck in this thread. All generations are welcome. One submission per member—please do not post multiple photos. Submissions are open now and will close at 11:59PM on 7/31/2025 from the time of this post. 🏆 What You Win:The winner will have their truck featured on the front page of the Mopar1973Man Gallery starting August 1st, 2025. 👥 Not a Member Yet?Join the community! It’s a great place to share your build, ask questions, and learn from fellow diesel/truck enthusiasts. Let’s see those builds—good luck

Sort of an update here: I found the lift pump wiring pulled out of the backside of the connector... I don't know when that happened.. Maybe when I was reinstalling the harness? I'm going to get a new connector for it. Basically the truck was running like **** because there was NO LIFT PUMP. Hope the little bit of idling I did with it didn't hurt the VP!

Took some time after work today to try to figure out whats going on with the truck.. still no real diagnosis now. I noticed when I start the truck it runs normally for about 7-10 seconds before it starts idling weird and misfiring. Here's a VIDEO of what its doing now. I'm about this 🤏close to just selling it like it sits. I'm frankly tired of working on it and even more tired of spending money. I'm still not getting any codes... no real path to follow now.

The only code is the lift pump code and the oil pressure sensor code for the faulty oil pressure sensor ( the lift pump code has been there for years. I have an in tank factory conversion that i bypassed for my raptor lift pump, so the plug is disconnected causing the code)

UPDATE Got the wiring harness back in the truck! While I was in there, I also did the WT mod: Alternator power wire is now routed to the passenger side battery The ground splice near the VP has been removed, properly soldered, and terminated on the backside of the timing cover case All good on that front. Now the new issue: Fired up the truck and it’s definitely misfiring — both at idle and under throttle No codes thrown (verified with a good scan tool) The only code-related issue is the ABS light, which wasn't on before When I press the pedal to the floor, it’s slow to rev and misfiring badly and smoking. Ran out of daylight to dig deeper, but that’s where things stand for now. On a positive note: When the idle randomly smooths out, the knock disappears and the truck idles great — so I think I’m slowly getting somewhere!

Sure did! Resistance tested and load tested every thing. No issues found. No crushed wires, no cut/damaged anything. The mystery continues!

Small update: Been real busy at work and general life events! Sorry! I got the Tesa tape in the mail today and finally had a minute to re-wrap my harness. I've never worked with this stuff before. It goes on easy and looks so professional, and apparently holds up well under engine heat. Only time will tell if that's actually true though! Look at all that old grimey, brittle and sticky plastic loom. Feels good to get that off of there!

So far I have found nothing! It's not difficult, just time consuming. I have this old power supply that I'm using to help load test the wires! Good to know! Im a cheap *** and prefer to struggle my way through this LOL.

Well, I decided to pull the engine harness. I want to completely strip it down and go through EVERY wire just to eliminate the possibility of it being a harness issue... The amount of man hours I have into this issue is actually insane.

Looks like you're going to win by default, but also this is really a great photo!

I've actually swapped in a know good ECM. It seemingly helped for a few miles and then returned to knocking. I might have a video of before and after the new ECM somewhere come to think of it! It's hard to tell in this video but the knock appeared maybe a mile or two after the "used but pulled from a running truck" ECM. Almost like it relearned this behavior after a few miles. VIDEO

Thank you for the clarification. I'll give that a shot. I'm on my phone now, so this will be a little less wordy reply lol. I checked the tone ring. No missing teeth (except the one thats supposed to be 😅) and it wasn't loose or movable in anyway. I had had my brother in law rotate the engine over while used my inspection camera to verify it's condition. All good from what I could tell.

Thanks for the reply! It sounds mechanical, but the fact that I can make it go away makes me think its not. If it were, it would be there under all conditions I would believe. "Have you partially blocked the exhaust to see if there is a steady miss when the sound is occurring?" - I'm not sure what you mean by this? Can you explain? "Have you removed the valve cover to see if anything unusual is happening - with or without the engine running?" - I have. Many times. It all seems fine. Nothing appears to change valvetrain wise if I do those procedures with the valve cover off. Not that I can tell. All looks normal. I should add that I have adjusted the valve lash and checked it many times. All within spec. "Can you detect if there is a cylinder miss when the sound is occurring?" - Doesn't appear to be missing. It sounds like over advanced/retarded timing to me. Like the fuel injection is happening too soon or too late causing this sound. It can be heard through the lower end of the rev range, but seemingly smooths out under load, but it's hard to tell. Like I said above, I found ONE other person ( I've been searching for years to find someone that had this issue ) just last week that had the same exact sound as my truck. Even the exhaust note was the same "choppy/stutter" sound. He fixed his by replacing the crankshaft position sensor. I had already done that, but I replaced it again just for giggles. I've Ohm'd out every sensor and sensor wiring on the truck and have yet to find a fault. Having said all of that, the only thing I haven't changed on this truck is the batteries. They are from 2018. I'm going to buy a set of batteries and possibly do the W-T mod as well. I don't suspect any of that will help, but it can't hurt! Well.. It does hurt my wallet!

UPDATE: I ordered a Cummins OEM Crankshaft Position Sensor. I got it installed today. Unfortunately no change. The truck is still behaving the exact same way. So I guess my journey to figure this out continues. I am starting to lose hope again. I think my next step is to buy the Quadzilla tuner again (I had it on the truck before, but it died on me and was out of warranty so I never bought another one) at the recommendation of MoparMan. He says the quadzilla has the ability to data log actual timing and compare it to commanded timing. I'd like to see what changes when I end the kill test (causing the knock to go away). Maybe that will help point me in a new direction.

Hey buddy! I don't know the sizes, but you can likely find another bolt on the truck that will fit it to help you gauge diameter and thread pitch at least. Then take that info to your local hardware store and get the right length!

Hey everyone, I’m excited to announce that I’ve officially taken on the role of Gallery Moderator here at Mopar1973Man! I’ll be working to keep the photo gallery fresh and active by featuring member trucks from all generations! To kick things off, we’re starting a Truck of the Month (TOTM) photo contest! 📸 How to Enter:Post ONE photo of your truck in this thread. All generations are welcome. One submission per member—please do not post multiple photos. Submissions are open now and will close at 11:59PM on 6/30/2025 from the time of this post. 🏆 What You Win:The winner will have their truck featured on the front page of the Mopar1973Man Gallery starting July 1st, 2025. 👥 Not a Member Yet?Join the community! It’s a great place to share your build, ask questions, and learn from fellow diesel/truck enthusiasts. Let’s see those builds—good luck!