The engine could stall in the middle of driving because of misfire. my lexus 250 only 40k mileage and always do proper maintenance to the engine every 3000 mile. i do research that lexus is 250 cause carbon build up because of the wrong design of the direct injection. here's the youtube link: https://www.youtube.com/watch?v=ytquqflawr8. i brought the car to lexus dealer, they won't admitted, instead they blame me using a wrong fuel. before i used 91octane shell, then i switch to 91octane chevron. still has the problem. they should recall for this matter, because it's about safety and the engine could suddenly stall in the middle of driving.