So I got this Mustang 2 years ago. A 2012 5.0 GT with a 6spd one of my childhood dream cars I could obtain and got it. 1,000 miles in after buying a phaser took a crap (chip on the inside of the phaser) and I redid the whole timing. Such a long tedious money consuming process but upgraded OPG’s, crank stud and gears. Redid the gas filler neck for the evap code and that fixed it cars perfect now for summer. Had it two years and haven’t even put over 3500 miles on it… it hurts I love the car when it runs solid. The engine clutch and trans were all replaced before I got it from a dealer with all the sheets and it looks solid. 

I just got it out last week for the summer and warmed it up drove it around the block couple times never getting out of second gear.

Today I drive it with my fisnce and kiddo and the car has an intermittent misfire on cylinder 8, I thought maybe bad gas? It was on E from last years gas so I filled it with premium. Had an intermittent misfire on cylinder 8, check engine light would randomly blink here and there maybe 3-5 times in a 40 minute drive. It pulled nice, did a burnout nice, but every couple pulls it would blink so I figured it was a spark plug or coil pack. Here are the 4 spark plugs from that side of the engine. The cylinder 8 is all the way on the right at the start. Smells like fuel not oil more like fuel. I’m thinking maybe an injector if the spark plugs and coil packs I have ordered don’t fix it. 

Hoping these spark plugs help but what do my fellow mechanics think? I’m a 24y/o just busting his ass in the dad life rebuilding classic cars for a living and trynna have a fun car the kiddo loves. Thank you for all your help, as I do all my work myself, my whole life never once took my car to a dealer. That timing job was a close one but I did it, and super proud how far I’ve come. Just these little things scare me after the timing job. My daily took a dump but it’s cheaper to fix the mustang if it’s just spark plugs, and more fun to drive. The other car needs some suspension and wheel work. 

Thank you again! 

Hopefully just a spark plug right?