1996 Other Oldsmobile Models Engine Cutoff Noises

Noises problem
1996 Other Oldsmobile Models 4 cyl Wheel Drive Type unknown Automatic 140000 miles

When I start the engine, it cranks very quickly with no hesitation. Almost too quick, sounds like a flywheel grinding for about a half second before I let go of the key. Also, when I turn the ignition off, the engine cutoff is very abrupt. Sounds like the engine seizes up. No natural (second of wind-down), just 'zzzztt', off. Any help would be appreciated. Thank you.