How do these plugs look? (5.3, AC Delco plugs)
 

Trying to diagnose a slight roughness at idle, so I took out the plugs from the driver side bank only (1,3,5,7) for the meantime, just to see what I could see.

Other than what looks like oil on the threads, the electrodes and firing tips look alright but I did notice a slight discolouration (pinkish) on the insulation of 1 and 3 mostly, and slightly on 5. All were still gapped to approx .040 as per stock.

Lemme know what you guys think.

http://farm5.static.flickr.com/4147/...13ba6fac_b.jpg

http://farm5.static.flickr.com/4153/...fa8b1638_b.jpg

http://farm5.static.flickr.com/4088/...7c3d3e9a_b.jpg

pull the other side and compare....i can't see how your truck already has oil on the threads. are you getting any oil in the intake runners?

Ya I'll do the other side probably tomorrow. Unless motor oil is used as a lube/antiseize from the factory, I'm not really sure how it could creep past all the threads...I'm not seeing any signs of burning oil either, tail pipe or oil level going down.

I haven't had the manifold off yet, but when I switched throttle bodies I did wipe inside the plenum and there was some oil film, but nothing too crazy.

In the spring when I change the cam I'm going to reconfigure the PCV routing with a catch can to pull from the crankcase so I'll see if that makes a difference.

looks like you have it planned out man. i put a catch can, and i love it. the only bad thing is i have a Evap code now lol. deleted them out the tune lol

Dude when i did my headers at 40k miles i check the spark plugs.. there just like that.. so i replaced the # 40-110 ac delco i think thats the part number... iridium.. i have 45k miles on it and i just check it and there like new... but also i got a heavy foot lol