Yes, direct injected Toyota 4gr-fse. Has to be one of the worst engines ever engineered. Thank The Lord us jeepers will never have to deal with valves that bad because of the fuel spray on the back of them. However it can still arise in other areas, as will engine sludge.
Those Toyota motors get so bad, the carbon builds up on the valves, and piles up on top of the piston, essentially changing the compression ratio, and causing ridiculous misfiring and rpm surging. I'm not talking at 200k miles either. The one pictures had 46,000. Their solution? Newly redesigned pistons and rings, and a full engine teardown/clean/rebuild.
Take car of your jeep and follow the scheduled maintenance intervals, and you should NEVER have a problem with sludge or carbon. BG44k works great as a preventative measure every couples of tanks, but by no means is an induction service a remedy for an already present issue.