Hello, my mum is currently having a typical MAF problem, where the car won't rev over 3k on the motorways and sometimes slows down to as little as 40mph (up hill) and can't go any faster. Been reading this is a well known MAF problem, and told to clean the MAF sensor out. Problem is, it has 2 security screws. They appear to be Torx T20, however the screw isn't a Torx. Torx has 6 sides, these screws have 5. What on earth tool will I need to undo this? Too expensive to get audi to fix it, and probably won't need a new one, just needs a clean.