Well I got underneath it and used my stethoscope ( a screwdriver) and listened. No noise from the pan so that's reassuring. I'm thinking it's an exhaust leak on the drivers side around the flange or o2 area. Seems to be very relevant there. If not, I hear these cars can get loose rockers? Or maybe a lifter issue? If its anything like my GTP are the rockers torque to yield or are they adjustable?