Hi Guys can someone please give a little mechanical assistance... was driving the S3 today and the LOW OIL PRESSURE warning light came on, another mile down the road a loud rattle/ vibration noise seemed to be coming from the engine ( kinda like a diesel car type sound) in 4th with low revs and when changing gear it was at its loudest, in 3rd with a little more revs noise still there but not as loud.. is this serious or an easy fix??? Thanks in advance for any help..