I recently took my 91 mustang to get dyno tuned. The bearings, head gaskets and piston rings have about 350 miles on them and the heads have about 10000 miles. The tuners had to stop due to excessive oil burning. When i open up the butterfly on the throttle body, there is smoke coming up through the intake. How do i tell if it is coming from the oil rings, valves or guide plates. Thank You.