Tow thing could be at play here. It could be as simple as low fluid level - to be checked with engine warmed up, at idle, not off - or the cable adjustment going into the transmission may need to be re-set. The latter job is a bear, and a good result come more from trial and error than procedure. The movement of the cable itself is infinitesimal. We are talking in the sixteenths of inches difference between drive and neutral. There is an adjustment plate where the cable enters the transmission. Once, I got a huge difference in performance simply by un-doing the nut and retightening it immediately, with no perceptible movement to my eye. Hugh