Note On Intermittents
WARNING: This page is about a different car, the 1995 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
Check for intermittent short to ground in circuit No. 434. A stall or a near stall condition which may set Code P054 or P095 and may cause a false Code P091 to set due to engine transition from running to not running (or near stall) then back to running without transaxle switch being in Park or Neutral.