NHTSA Complaint #11487246 — 2014 MERCEDES-BENZ E350

I brought in my car to M1 Mercedes, Fremont, CA for service after “check engine” light was on and running rough on idle. I told them I started using ethanol (E85) fuel recently but my car is spec for that. The shop replaced spark plugs and ignition coils but the issue didn’t go away. While the car is parked overnight at the shop garage, on Jun 21, 2022, around 11pm, the engine exploded. The incident was caught on camera by the shop. The intake manifold was blown open. The car was tolled to Fletcher Jones Mercedes Fremont, CA (authorized Mercedes dealer) for diagnostic. However, they didn’t offer any solution or attempt to find out what caused the explosion. They offered to replace the intake manifold for $1200. I declined as I believe this is a serious safety issue. What happen if it explodes again? Since the cause of the explosion is not found and address. It could happen again anywhere, anytime. Fletcher Jones Fremont charged me $265 for labor and I tolled my car back home. I attempted to contact Mercedes USA via their website to alert them about this problem and seek resolution. However I never hear back from them. I hope you can help to look into this serious safety issue. Attached please find the blown intake picture and report from M1 Mercedes. I have the explosion video as well.