Another P0307 at 14,400 miles

I have 2019 Tundra SR5 Crewmax with a 3UR-FE engine. At 7,240 miles I got a P0307. Dealer replaced spark plug under warranty. Last week at 14,400 miles I got another P0307. I drive it about 2000 miles a year on trips that last about 40 minutes - 3 times a month . Scheduled an appt at the dealer and it is 3 weeks out. I replaced the spark plug myself, cleared the codes and it seems to run fine. Any thoughts on why that cylinder 7 plug keeps going bad?

 

Try swapping a coil from the opposite bank. If the code moves to P030x (even #) you’ve narrowed the problem to that coil.

you could swap coils on cylinders from the same bank, but opposite bank (2) isolates the harness as well as conditions specific to bank (1).

Just wanted to confirm bank order before specifying Bank 1 drivers side, Bank 2 passenger side

 

Swap #7 coil and injector with another. If it comes back you can narrow it down to those components or and internal issue.