2000 audi s4 6 speed first of all i think its in limp mode its only boosting 5 or 6 pounds of boost on my boost gauge i just got the car so i dont know how long its had this prob and also my oil dip stick stinks like gas real bad i changed the oil when i first got it and checked it about a day ago and it stinks again i need help with this real bad i heard this is not good at all for the car

 

do a compression test, could be piston rings?