Award for worst Spark Plug?

My guess, Oil blow-by & too many miles on those plugs..

You can get an iridium spark plug that will out-last oem spec and match performance such as:



Do you ever "Floor" it? I see this type of carbon build up on intake valves/plugs when motors are over babied..

PS: Forum search "Oil Catch can"..

 

This ^^

I used to own a Suzuki Samarui that burned so much oil I could get maybe 200 miles before fouling the plugs... I got really quick at pulling them out and cleaning them.

That motor was a POS.

 

I have a Ford 5.4 3V with this issue, he is correct. The previous gen 2V 5.4 Ford motor was a gem as well - the spark plugs blew out of the head due to only 2 threads holding (not!) them in. Luckily, the redesigned plugs don't break, but the 3V is a horrible design and you must change the plugs about every 20k or they are a b#tch to get out. The original plugs broke so often, Ford had to invent a special tool to extract the broken piece from the heads.

 

I had a 2005 Ford Exped that had absolutely nothing wrong with it right at 100k. At 100,250 miles it developed a weird stalling issue that I believe was something to do with the cam chain tensioner. Ran great till it fully warmes up and then it would stumble really bad when you came back down to an idle. Blip the throttle and all was good again.

Decided I may change the plugs being they were still the factory plugs.

I purchased (and still have) the extraction kit. Every time I got all set up to replace the plugs, my gut told me not to. Felt like I could be doing head work or something.

Screw this!

Traded it in on a new 2016 Corolla. Got exactly what I hoped to get, given the crappy resale value of it.

Made sure to park it within a mile of the dealership the night before so when I took it in the next morning, it ran perfect for them.