My 2013 Yukon XL 1500

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BigDogYJ

BigDogYJ

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If it were me, I would disable the AFM. Why take a chance of that happening again. My truck has 205k miles, AFM disabled and running good.
Yup. I'd love to get it disabled but I need to get it to pass CA smog first. Unfortunately this bit me in the butt today.

So I screwed up....

I was driving it around today to get the monitoring tests to pass so we could smog it. Well I was driving it with the trans in M5 and it was passing all the tests without going into v4 mode. I messed up and shifted to M6 and it went to v4 mode and collapsed the lifter instantly and cyl 6 misfire started instantly. Damn...

So I should have been more careful to make sure it wasn't shifting to 6th. Oops.

So tomorrow I'm tearing back into it again and gonna do it all over again.

This time I'll make sure it's in M5 only so it doest go to v4 mode so I can get it to pass the smog check. once that's done I can tune the AFM stuff so it doesn't happen again until I can get the AFM delete done.

Wish me luck.
 

swathdiver

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Yup. I'd love to get it disabled but I need to get it to pass CA smog first. Unfortunately this bit me in the butt today.

So I screwed up....

I was driving it around today to get the monitoring tests to pass so we could smog it. Well I was driving it with the trans in M5 and it was passing all the tests without going into v4 mode. I messed up and shifted to M6 and it went to v4 mode and collapsed the lifter instantly and cyl 6 misfire started instantly. Damn...

So I should have been more careful to make sure it wasn't shifting to 6th. Oops.

So tomorrow I'm tearing back into it again and gonna do it all over again.

This time I'll make sure it's in M5 only so it doest go to v4 mode so I can get it to pass the smog check. once that's done I can tune the AFM stuff so it doesn't happen again until I can get the AFM delete done.

Wish me luck.
The main reason that the lifters collapse is because the VLOM solenoids get out of time. It is SOP to replace the VLOM whenever an AFM repair is made.

AFM is not part of the emissions system and BlackBear tunes are undetectable.
 
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BigDogYJ

BigDogYJ

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The main reason that the lifters collapse is because the VLOM solenoids get out of time. It is SOP to replace the VLOM whenever an AFM repair is made.

AFM is not part of the emissions system and BlackBear tunes are undetectable.
Yeah I'd prefer to just delete the AFM parts altogether. But I'm afraid while an emissions test normally won't detect a tune, CA recently started doing the same check on Gas engines as they've been doing with Diesel's for a few years now. they scan the ECM for the CVN (Checksum Verification number -- I believe?) and look for any number that doesn't match factory or at least any CARB approved CVN. I talked to Black Bear performance this morning and he was confident their tunes wouldn't be detected as far as an emissions check goes since all the emissions tests are still enabled, but if they are checking CVN codes, they'd likely detect that modification. I'm planning to have a chat with a friend of a friend soon that's a CA smog tech to try to understand exactly what they are looking for. I'm hoping simply turning off AFM in the ECM won't cause it to fail but gotta make sure before I remove all the parts. If that works then a full arm delete is at the top of my list. Thanks all.
 
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BigDogYJ

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Ok got it tore all apart again. Lifter only too two small taps to pop free. Got it all back together. Took about 4 hours from start to finish until it was ready to start. Drove it for about 30 minutes and 5 of 8 monitoring tests completed. Hope to get the others to finish this weekend and then smog it. Then we can program afm out of it and work on a time timeline to source the parts and eliminate all the afm crap. Let’s hope it passes.
 

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