2012 Suburban Misfire #5 drama

[rdezs]

I used the Diablo predator to turn off the AFM, and make a few other adjustments like tightening up the shifts for longer transmission life. The total cost of how much you spend really depends on how much you want to do "while you're in there." For example, since I had my heads off which looked good, I figured why not have them checked out by my local cylinder head guy.... Cleaned up, valve job, all the guides are okay but new seals. With the front differential out and the oil pan off, you're looking right at the back of your power steering hoses on the back side of the pump..... It'll never be so easy to replace those again. New ACDelco starter as preventative maintenance since it's out anyway..... And the crankshaft position sensor is right above the starter, so might as well do that as well. The list can be extensive once you get down that rabbit hole, lol. Stuff like that really isn't necessary technically, but as this is my wife's daily driver I figured it was be a good idea.

I've been getting the genuine LS7 lifters from Michigan Motorsports. And make sure you use genuine GM lifter trays as well. Below is a picture off there website showing the gold retainer....

 

[Airman68]

I used the Diablo predator to turn off the AFM, and make a few other adjustments like tightening up the shifts for longer transmission life. The total cost of how much you spend really depends on how much you want to do "while you're in there." For example, since I had my heads off which looked good, I figured why not have them checked out by my local cylinder head guy.... Cleaned up, valve job, all the guides are okay but new seals. With the front differential out and the oil pan off, you're looking right at the back of your power steering hoses on the back side of the pump..... It'll never be so easy to replace those again. New ACDelco starter as preventative maintenance since it's out anyway..... And the crankshaft position sensor is right above the starter, so might as well do that as well. The list can be extensive once you get down that rabbit hole, lol. Stuff like that really isn't necessary technically, but as this is my wife's daily driver I figured it was be a good idea.

I've been getting the genuine LS7 lifters from Michigan Motorsports. And make sure you use genuine GM lifter trays as well. Below is a picture off there website showing the gold retainer....

I 100% get doing it while you're in there. I would do the same thing. I'll have to look into the specifics what needs to be done. I have done head work before and would certainly have those repaired while out. Fortunately, mine is running good now (knock on wood) but it's always nice to have a plan so you're not caught off guard when it happens.

 

[Doubeleive]

Noid light on injector 5 was flashing at steady pace without problem and when plugged back in the miss decreased again by half of what was evident when unplugged. Time to start shopping AFM delete kits with a tune I’m guessing

@198k my next test would be a backpressure test, then if that doesn't reveal anything I guess crack it open
backpressure test is easy enough to do with some basic hardware and a gauge
unless there's a better idea......
I am speaking from the perspective of I went the route of replacing lifters to then finding out a clogged cat was (at least) a good part of my issue.
still kind of mad about it.......at myself
my case was more severe I had multiple unexplained misfires and rotational noise, loss of power, but didn't fully diagnose the possibility of a clogged exhaust

 

[Geotrash]

I'm a pretty capable mechanic. What would you say your parts cost and how much time did you have into it? Also, did you get your computer reflashed? I bought a truck from a guy many years ago, and he did these and said he reflashed the computer to delete the AFM stuff after installing the parts.

I had Blackbear tune mine and it's been great. Here's my thread on it for my 2012 6.2 if you're interested. I'm also very happy with the cam I chose. Smooth idle and great power down low.

https://www.tahoeyukonforum.com/thr...nali-6-2l-cam-swap-thread.121671/post-1616690