L29 0411 Swap - Struggling with crank relearn and P0300

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BeXtreme

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Awesome yeah I'm in Newberg, not too far from you.

I'm going to give another crack at this disabling the range selector code - I already tuned out PRNDL and have a wire I can use to ground the two pins set up....

Let me see how this next attempt goes and maybe I'll hit you up. I have full house HP Tuners, what freeware are you using?
I've got an OBDXPro Vt tool and use PCM Hammer or LSDroid to read/write and TunerproRT or Universal patcher to modify the files. I wanted to learn on some nitty gritty stuff first, but I have a HPTuners bundle in the mail right now for my 2011 Suburban and other stuff that I couldn't tune with the free stuff.
 

69project

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I did a 411 swap on a L31 (actually GM 383HT) and have had a lot of issues and this was one of them. Mine never did the crank relearn even though it needed it. I had to go back on my scan tool and look up a 1997 L31 and see where the distributor was set and then adjust it to make sure it was +/- 2 degrees, not sure what the L29 requires. At this point since you have so many misfires, I would also check your plugs to make sure none of them are now fouled and also check your wires. I also had that problem which really affected things and my tuner couldn't tune the truck because of it. I would do a fuel balance test or whatever they call it on your scan tool to check to make sure all of your injectors are pulsing. On my 383 I discovered one of mine wasn't because it wasn't fully seated in the injector hole, it would spray fuel in the intake manifold but since it wasn't fully seated in the injector hole the fuel wasn't going into the combustion chamber like it should. I am not quite sure how the L29 is set up for it's injection but I know it's different and I don't think L29's have nearly the heartache and frustration like the spider injection is for the L31. Good luck.

Sounds like your better equipped to deal with this since you have an HP Tuners. Remember this is a fuel, air, and spark problem. I will assume you can eliminate air as a potential issue so that leaves fuel and spark. I would work backwards from the combustion chamber and see where it takes you.
 

Mangonesailor

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Go into the table for programmed DTCs and unselect the range sensor box, try again maybe? I'm fairly certain there's a discussion in either the 454 thread or the thread for my truck that addresses the problem directly?
I remember now we had to do that for your truck.
 

Brav302

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I completed my 0411 swap today. I couldn’t get the relearn to work until I selected 2002 8.1 as the powertrain option relearn was successful on first attempt. No other issues or DTCs.
 

Mangonesailor

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I completed my 0411 swap today. I couldn’t get the relearn to work until I selected 2002 8.1 as the powertrain option relearn was successful on first attempt. No other issues or DTCs.
Let's be clear for the boys and girls at home.... You did this with a tech 2 handheld scanner, correct?
 

Reluctanse

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tomorrow i will test this thing again disabling the trans range error code.... I will post up results.
 

Reluctanse

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Well today's saga seems to have some good news-

Disabled the P0706 range code, then did a relearn.
As stated above, it revved to about 3500 then dropped. I shut off and restarted. It was immediately better and driveable, so I took it around the neighborhood. It had a few slight misses that I could feel but nothing like before. In short, I think that did it.

I am logging misfires though and watching, still getting a few random ones logged. Not enough to trigger any codes. #4 in particular is a repeat offender... so I pulled the plug just to see. It still looks brand new. As it should, because it is.

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I also note, that it only really occurs under light throttle/cruising ~25-35 mph. More on that in a sec.

I also am reminded that there is a need to replace the injectors on this rig, hard starting especially when warm is very prevalent, and it also smells like fuel when I open the intake track up.

Prior to the 0411 swap, I would notice weird surging/missing at minimal throttle, like foot just on it, again cruising at light throttle, 25-35 mph and hardly touching the gas.

So now I'm going to theorize my issue with #4 is injector related, as was the surging I noted.

I need to go for a more involved test drive to confirm I have indeed gotten this issue behind me, but first, I need to re-seal the water pump I just put in..
 

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Reluctanse

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welp it's worse than ever.

got the water pump swapped, so thats good to go.

Truck idles but will have an occasional miss.... touch the throttle at all and it sputters and chokes and stumbles, I can barely get it out of my driveway. It also backfires now. Definitely timing related, but... what do i do to fix it??

Crank relearn seems to -work-? I get the idle cutoff, then cycle the key. Wonder if I'm still missing something.

Anything you guys got, hit me with it. I have the hp tuner logger, but I don't even know what to look at at this point.
 
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