Help reading plugs

Joined
Feb 24, 2005
Messages
1,905
Location
Southeast Louisiana
2019 Ram 1500 5.7 liter

Check engine light came on a couple weeks ago after replacing battery. Thinking it was related to that I disconnected negative battery cable to clear it. Today, the light came back on so I went to Autozone and had it read. P0304, cylinder 4 misfire. Well schucks, I am full aware of what that could be indicative of but I am doing my due diligence. I changed the 2 plugs and swapped the coil to cylinder 2 so we will see. Below are pics of the 2 plugs I pulled out of that cylinder. Truck has almost 105,000 miles. Can someone who speaks fluent spark plug take a look at these and tell me what they speak to them?


IMG_9739.webp
IMG_9738.webp
 
With that tan ash buildup it could be running lean. Possibly a clogged injector? I would run Techron and see if it resolves. That's if your plug and coil swap doesn't reveal a spark problem.
 
With that tan ash buildup it could be running lean. Possibly a clogged injector? I would run Techron and see if it resolves. That's if your plug and coil swap doesn't reveal a spark problem.
I will try that as that could possible trigger a misfire as well.

I can’t really determine wear with these iridium plugs. Do these look worn enough to trigger a CEL? I know they aren’t the originals.
 
Plug on the left looks like it lost a piece of the ground strap making the gap a bit wider, but with that kind of milage think just replace the set.
 
I hadn’t noticed the ground strap. In the pic it looks like the left plug rolled up a little bit. I kept the ones I took out abd will definitely reexamine and post more pics tomorrow.
 
In the pics it must have been that the one on the left is turned a bit, I looked at them again this morning and they are pretty uniform, ground straps intact.

The CEL did turn itself off though, so I will go ahead and replace the remaining 14 my next day off.
 
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