Misfire on DOD cylinders

[Ceejkay]

Back with a new to me truck. Just got a 2010 Escalade with the 6.2 awd. 180k miles. Been about 8 years since ive owned a gm and little rusty in the troubleshooting.

Truck idles decent in park. A little miss, But when in gear at let's say a stop for a min or 2 it starts misfiring bad and the stablitrack lights up and flashing cel. But as soon as I go within a few seconds it clears. Doesn't feel low on power. And the lights clear. Ran the misfire log on my tech 2, cylinder 4 is the worst followed by 7, 1, and 6. I believe those are all dod cylinders. I bought it used and they did plugs, oil and a few other things and it has the dod obd dongle but the dod delete doesn't appear to be done.

I did check the gap on #4 spark plug and it's good and looks new, they are ac delco plugs. Swapped #2 and #4 coil pack and wire and the problem didn't follow. I don't hear a lifter tap at all. I haven't pulled the valve cover to check yet as it's a little sketchy to do it in gear as that's the only time I really get it. The dod delete with a cam and a few other goodies are going to happen in the future but wanted to get a decent baseline. Any suggestions?

 

[donjetman]

@Ceejkay
Add a catch can. There are hundreds of post here on the subject. Spend a little or a lot, your choice:
https://www.tahoeyukonforum.com/threads/get-a-catch-can-before-any-mods.49716/page-53#post-1288561

Has the the TSB about replacing the poorly designed driver side valve cover been replaced?
https://f01.justanswer.com/ebrock63...il+Consumption,+MIL+ON,+Engine+Runs+Rough.pdf

 

[Ceejkay]

@donjetman ill look into that, it's a new to me vehicle so who knows what's all been done. They did do a tb cleaning before I got it and it did take a couple drives to show up. But on the same hand I've only put about 15 miles on it and haven't really got on it.

 

[swathdiver]

Make sure the plugs are all gapped to .040 and while hard to tell, make sure they aren't the counterfeit 41-110s. Check the wires.

If you do a leakdown and the pistons are good, turn that L94 into an L9H. I say this because people buy those high performance trucks and feed them a steady diet of 87 octane fuel and over time that wrecks the pistons and rings.

Have you checked the trims too? Any exhaust leaks or broken manifold bolts?

 

[Ceejkay]

@swathdiver I did check the gaps and wires. And I couldn't tell you if they are fakes or not. I would be lying if I said I knew what I was looking at for fuel trims. No exhaust leaks that I can hear. And I'm a firm believer of 91/93, my other car is the new Ranger that has never seen a tank of lower octane other than what the dealer put in it when I bought it.

 

[swathdiver]

Well, make sure she has some Top Tier 93 from somewhere or even E85 and check the alcohol content in Fuel Trims with the Tech-2 to make sure it's not out of whack. Than have a look at those misfires again.