i have a a4 2004 1.8t 95k, i getting the oil preasure light come on. i took it to get a preasure test done @50psi at 2k rpm @75psi at 3k rpm. every thing i read said for me to change the pick up tube. is that all i have to change or should i change other things while i am doing the job? is there diy for it? thanks