I have an a4 1.8t and I can nit for the life of me figure out my cars problem. It starts with boost problems I have a stage 2 apr chip. At full throttle will boost to 8psi, problem! But if I let off the throttle to about half or quarter throttle the boost will shoot back up to 18psi and will continue to stay there if I put the throttle all the way down. And just yesterday ive been getting rough variating idle. And also my crank case pressure is extremely high! Popped my dipstick out and oil shot everywhere! Anyone have any of the same problems as I do? How the hell do I fix this?!

 

Maybe something PCV-related? Pressure should certainly not be building up to the point that when you pull out the dipstick oil shoots everywhere. Your abnormal idle leads me to think there is an issue with vacuum hoses.