Same story. $8000.00 to remove and clean the heads!! This is getting crazy. Premium fuel, 8.00/litre oil, 70K miles and this is what happens. I am really really dissapointed in BMW. Of course my warranty company is denying the claim because "Carbon" and other deposits are not covered. I am going to run Auto RX in the engine and see if that unplugs the carbon - once and if that happens I am driving straight down to the Lexus dealer and ridding myself of these cars. They drive beautiful but are poorly engineered - plain and simple.