Truck has been running rough on cold start for about a minute or less for a while now, didn’t pay much attention to it.
Now yesterday it got rougher and didn’t go away, then got bad in drive around 1-1.2k rpm.
Finally engine light popped up for few seconds and i was able to read it as cylinder 2 misfire.
Swapped wires, still cylinder 2.
Spark plugs are less than a year old, maybe 10k miles tops, NGK TR5.
Took out the plug and it looked fine, clean!
Replaced single plug with NGK TR5IX, runs smooth again and no rough idle on cold.
Never seen a single plug go bad!
Also got a top engine cleaner just in case, might run it over the weekend