I believe there are 2 plugs that look the same and can be swapped. Make sure they didn't get crossed.
2006 Lexus IS350 Smokey Granite Mica w/ Sport pkg
Megan EZ Street | F-Sport Rear Sway Bar | 2012 ISF Steering ECU
18" TSW Nurburgring wheels | Injen Intake | M2 Catback exhaust
Roadrover navigation + backup cam | 2 10W6 JL subs + JL 1000/1
6000K headlights + fogs | OEMthing spoiler + roof spoiler | F-Sport Grille