L29 0411 Swap - Struggling with crank relearn and P0300

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Reluctanse

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OK I am struggling to get this thing to run right. Here is what has transpired to date:

1. Swapped in the 0411 ecu using Lextech pinout
-here I included 2 wires out from C1: Pin 32 and 34 that I can ground for crank relearn
2. Using HP Tuners, reflashed ECU to the 2002 Express Van 5.7 tune
3. Edited tune to work for the 454 (VE table, spark table, MAF, VATS delete, PRNDL disable, fuel cut and shift tables from black box)
4. Attempted a crank relearn. Followed the exact process here:
Little note I'll post here and in the 454 thread that we figured out together. To perform the CASE relearn on the 0411 with the GMT400 (/keywords) Pins 32 and 34 on the Blue C1 connector must both be grounded. Then, apply the E-brake, apply the normal brake, and start the engine. Launch the scanner software, initialize the Crank relearn function and within 3seconds of pressing "OK" on the pop-up just put the accelerator to the floor while also pushing the brake. The CEL should turn off and a new pop-up showing the Crank relearn was a success should appear... then you can have a beer (and start checking for misfires at idle so you don't get a P0300!).
Did it work? I guess not, see below

-At this point the truck would fire up, run, and drive reasonably smooth.

5. Replaced the water pump, spark plugs, and wires. This may be anecdotal but I'm going to include it.
6. Now I am getting a P0300 and heavy noticeable misfire under just about any conditions, although my logger does not seem to catch it very often. By my best guess, the logger will show 1 misfire for every 10 that I can detect.
-here I re-checked all the spark plug wires and made sure they were tight. Didn't notice anything out of place.
7. From another post it was pointed out the rev limit in the tune needs to be stock. I had lowered mine to match the black box. I adjusted this in the tune to 5600 and tested relearn again.
8. Again following the exact above instructions, truck revs to 5600, hits fuel cut. I see no alerts from HP tuners that the learn was successful, and the misfire is worse than ever.
-I will note that the P0300 does not show a check engine light, but only comes on as "Pending" in HP tuners.

Any thoughts I would appreciate it!


Here is a link to my tune file in HP Tuners if that helps any https://1drv.ms/u/s!AiAQ2z0w3tlozkUjYbCK0asXqyq8?e=gGKc2I
 
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Mangonesailor

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Pull your dizzy, the drive gear is probably toast. Same thing happened to me. I had to replace the gear and my P0300 went away. If you look at the total misfires per cylinder and the firing order you might find they're clumped together in the firing order. That'll show if it's the drive gear or not.

Go to Auto zone and get their Gold level dizzy/cap/rotor assembly and stab it in. It's got everything you need, ready-to-go. Plus lifetime warranty and brass contacts. I usually have to replace the dizzy cap in my truck every 10kmi due to hard to start issues or misfires. So far I've made it almost 20kmi without a problem.
 

Spareparts

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Make sure your cmp is within + - 2.
Mine would not relearn either so black bear tuned it out. Truck has no miss fires I can feel.
 

AuroraGirl

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crank learn is to determine where the balancer is in relation to what timing is at a certain rpm(Fuel cut off) so it can establish criteria to discriminate road harshness from engine harshness on knock sensing and misfiring counting.
If you misfire sitting still your issue needs to be fixed before it can do that learn I bet
 

AuroraGirl

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Pull your dizzy, the drive gear is probably toast. Same thing happened to me. I had to replace the gear and my P0300 went away. If you look at the total misfires per cylinder and the firing order you might find they're clumped together in the firing order. That'll show if it's the drive gear or not.

Go to Auto zone and get their Gold level dizzy/cap/rotor assembly and stab it in. It's got everything you need, ready-to-go. Plus lifetime warranty and brass contacts. I usually have to replace the dizzy cap in my truck every 10kmi due to hard to start issues or misfires. So far I've made it almost 20kmi without a problem.
does your distributor have a magnetic pickup? (to the OP) or just a magnetic trigger? Idk about the newer kind of distributors like a 2000 would have, but if they have a pickup coil then it should have 2 magnetic poles which can be felt by carefully rotating out of vehicle. Also it can be tested for by putting engine in bypass and then running at a certain RPM, the advance on a timing gun check would be moving all over if its weak, but should be consistent if good
 

Reluctanse

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Well thanks everyone for the replies so far.

Pull your dizzy, the drive gear is probably toast. Same thing happened to me. I had to replace the gear and my P0300 went away. If you look at the total misfires per cylinder and the firing order you might find they're clumped together in the firing order. That'll show if it's the drive gear or not.

Go to Auto zone and get their Gold level dizzy/cap/rotor assembly and stab it in. It's got everything you need, ready-to-go. Plus lifetime warranty and brass contacts. I usually have to replace the dizzy cap in my truck every 10kmi due to hard to start issues or misfires. So far I've made it almost 20kmi without a problem.
I just put a brand new UMP unit in less than 500 miles ago. I did keep my old one around, but kind of doubt this would be it, as it ran fine on the black box.


Make sure your cmp is within + - 2.
Mine would not relearn either so black bear tuned it out. Truck has no miss fires I can feel.
Is that just disabling the code? Or do you know what "they tuned out"?

does your distributor have a magnetic pickup? (to the OP) or just a magnetic trigger? Idk about the newer kind of distributors like a 2000 would have, but if they have a pickup coil then it should have 2 magnetic poles which can be felt by carefully rotating out of vehicle. Also it can be tested for by putting engine in bypass and then running at a certain RPM, the advance on a timing gun check would be moving all over if its weak, but should be consistent if good
Not sure, but I could check the OEM one, it's on a shelf and IIRC they were identical.

Maybe I should throw a timing light on at idle and compare to what HP tuners says?
 

Mangonesailor

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Have you tried pulling one spark plug wire at a time just to see if it's only one cylinder misfiring? I mean, it sounds like it's not misfiring constantly, but I'd bet if you went cylinder by cylinder maybe you could tell which one WAS misfiring the most? Can you recheck your pins at the ECU and make sure all your injector pins are correct/fully seated?

Just stabbing in the dark here, did you make sure every single fuse under the hood was good after your first start-up? You wouldn't believe the random fuses that blow after putting in a 0411.

You should be able to log in the scanner which cylinders are misfiring, you should be able to graph this too so you can compare rpm/load as it happens.
 

Reluctanse

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Have you tried pulling one spark plug wire at a time just to see if it's only one cylinder misfiring? I mean, it sounds like it's not misfiring constantly, but I'd bet if you went cylinder by cylinder maybe you could tell which one WAS misfiring the most? Can you recheck your pins at the ECU and make sure all your injector pins are correct/fully seated?

Just stabbing in the dark here, did you make sure every single fuse under the hood was good after your first start-up? You wouldn't believe the random fuses that blow after putting in a 0411.

You should be able to log in the scanner which cylinders are misfiring, you should be able to graph this too so you can compare rpm/load as it happens.
I just went over fuses and we are good there.

I was thinking this was a relearn issue but sounds like maybe not? I’ll start doing some troubleshooting…

Can someone confirm for me if HPTuners will pop up a confirmation message on a successful relearn?
 

Mangonesailor

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I want to say it did....

What is your current cam/crank offset reported on the scanner? Are you recording the misfires per cylinder, and each cylinder's misfire history? Did you match up the misfires to the firing order? You should try to do some of the freebie checks if your cam offset is low enough but it still won't take.

It kinda sways me to that your relearn hasn't took because the way you describe it. The engine should rev up as you punch the accelerator, it will climb in RPM until around 3800-4200 and then "BAHHHHH" cut fuel completely and the engine will coast to idle speed (which is your cue to release the accelerator. If it took, I think you get a little cue that it took.

I or @BNielsen should make a video of the process. Maybe I'll get my extra pins put in and grounded and do a relearn for you to see you what it actually looks like and how the truck responds.
 

letitsnow

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Has anybody here done a 411 swap and not had issues? I am not being a smart ass, am curious.
 
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