2013 Lexus IS250 Engine problems

Valley plate leak due to the fact that toyota/lexus utilized the improper sealant and used the improper amount, leading to the heat exchanger leaking coolant once the original, inadequate sealant begins to disentegrate. This could cause a condition where the engine could fail and someone could get hurt. Furthermore, all isfs will eventually have a cracked rh manifold on the #8 runner. This can cause a fire hazard in addition to carbon monoxide poisoning.

Exhaust header leak, audible ticking sound once warmed up in drive

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.