Wow, those plugs were used up! I think it would be pretty safe to assume that with gaps that HUGE they were lacking a little in efficiency and I think that you will see some improvements in cold starting, acceleration and MPGs. With only 156K miles on the EX and those plugs looking that bad I'd bet that they were the factory original AGSF22WM plugs.

When I changed my plugs at 107K miles my worst one had a gap of .072 (.018 over spec) with the 10 plug average at .067 (.013 over spec), yours has the worst of the bunch at .088 (.034 over) and the average at .076 (.022 over) and I noticed improvements in all categories mentioned and saw my best ever towing mileage on the first trip following the plug change. With an average gap wear at 70% more than what I had, I am positive things will be looking better in all of your performance aspects.
Looking forward to some fresh mileage and performance updates.

 

yeeesh those are bad plugs.

 

Okay, so after yesterday's drive and this morning, I definitely feel it's more peppy in acceleration. I feel the new plugs.

Here's the rub...

I think I feel it misfiring.

When sat at idle every 5-10 seconds or so, there is the smallest of vibrations that lasts half a second maybe. It's very slight. You can only feel it in your butt when you're sat in the seat. I even have to turn off the radio to concentrate it's that slight. But it's there. I know it's there because it's intermittent. I've checked all the COPs and their connectors again. All is good. They are all seated firmly and locked in place. My guy used dielectric grease on the boot ends and anti-seez for the threads. This isn't his first rodeo, even with the Triton's. Thoughts?

I will continue to monitor MPG over the next two-three tanks to get an average.

Turns out my scanner won't recognise the $06 mode, even though it's advertised as so. It's only showing $03, $07, $10 modes. It's being returned. Otherwise I'd be running the Misfire test as seen above.

 

 

this one? If so, that's just a few bucks more than the scanner I bought so will swap them out.

 

i bought the MX version about 4yrs ago, that is the newer version so should work even better. MX+ version also includes the enhanced stuff for free on their obdlink app.

i have zero complaints about it, and the firmware is updatable

 

I've ordered the MX+ version.

Just had to go to the UPS store. On my way back I had to flip into 4H due to snow and upon acceleration, I heard a loud "ticking". Like it was from the cylinders.

As the temp is dropping, I gave it some revs in neutral once home and it was smooth.

This truck is slowly edging away from a curious project to a frustrating burden.

 

what were the plugs torqued too???? i would make sure they were at least 28ft/lbs. if they weren't and were only torqued to the spec of 11 you could have a loose plug...

 

I told him to torque to 28ft/lbs. No reason why he shouldn't of.

Do you have advice on what I should do (test wise, info wise on Forscan) when my adapter arrives on Sunday? I'll be trying it with the Android app first - which I've already purchased.

 

Ticking or pinging?
Does your 6.8 have any missing exhaust manifold studs? If missing a few you will sometimes get a pretty good ticking especially with a cold engine. And if enough are missing that can cause enough of a leak to screw with the O2 sensors, which can cause it to run rich, which reduces the mileage...........
And I would maybe ask the mechanic about the torque value used, can't hurt and could save you from a plug blowout. "No reason why he shouldn't of" in a perfect world, yes, in reality there are uncountable reasons why he may have strayed from that request.

 

Is there an easy way I can check? My research says these bad boys are good and buried? I'm getting the Banks Headers in the next few weeks, so if this is the problem then that'll be taken care of in one fell swoop.

I called the mechanic and he told me he torqued to that spec and others he did by feel, quoting "when you've done enough, you know the feel when they are in there".

 

If you go with the Banks headers, that will take care of any exhaust manifold leaks it may have, and if you have many broken studs that job will take a while and will not be cheap.
Looking from above, below and through the wheel wells you should be able to see most if not all 20 exhaust manifold studs and nuts, I would expect that you have a few missing and that could be where your ticking is coming from.

 

especially if a MN truck for it's entire life.

mine was a WA/ID/MT truck and I was missing 4

 

I've got two missing. One on each bank.

Definitely misfiring as I feel rougher vibes when the truck traffic crawls at 750 rpm.

​​​​​Will wait for Forscan on Sunday and then go from there. I think a plug isn't seated all the way somewhere.