I just bought a 1998 V70 awd. It has 198km. I have had it for about one week now. Today, I raised the back end with ramps to repair a hole in the muffler by welding in a patch. After my repair, I started the car while it was on the ramps to check for exhaust leaks. Then I drove it off the ramps and brought it to my other driveway. It was then that I started hearing a ticking noise that was coming from the valve cover. I read posts left from Tech that it may be from the oil pan o-rings causing low oil pressure. Could the fact that the car was on an angle when the engine was running cause a temporary low oil pressure situation? Do you think the noise will go away? Is it dangerous to drive the vehicle when the noise is present? Would a change of oil and/or engine flush help the situation?