08 Tahoe help!! Cylinder #1 misfire

[Isaiah13]

I checked today to make sure I didn’t have a stuck lifter, checked compression it was all good. The #1 plug was the problem. Replaced it running fine now, engine light gone.

 

[wsteele]

View attachment 350356I checked today to make sure I didn’t have a stuck lifter, checked compression it was all good. The #1 plug was the problem. Replaced it running fine now, engine light gone.

Looks to be a tad more than .040"

 

[Fless]

Looks like more than 2 months' worth of wear on that new plug. Are you running platinum plugs, or iridium?

 

[OR VietVet]

Looks like more than 2 months' worth of wear on that new plug. Are you running platinum plugs, or iridium?

Exactly what I was gonna say. Something is going on in that cylinder. I also agree with @wsteele about the plug gap and would be curious what plugs you used.

Compression readings and comparison with cylinder #3?

Should be this plug: https://www.rockauto.com/en/moreinfo.php?pk=10351600&cc=1441040&pt=7212&jsn=911

 

[Fless]

You may have had some carbon tracking where I've circled in red:

 

[Isaiah13]

they are iridium plugs.

 

[OR VietVet]

they are iridium plugs.

Whose Iridium plugs?

 

[Fless]

Whose Iridium plugs?

And where were they purchased?

 

[Isaiah13]

Advance auto

 

[OR VietVet]

I guess I will ask just one more time, whose makes the plugs? Also, while I am at it, whose makes the plug wires? Compression readings compared between #1 and #3?

I promise, last time I ask these questions and then I just give up and will stop bothering you.