crankshaft sensor replaced 700 miles ago. codes cleared, however, catalytic conv.,oxygen sensor,and egr system show "not ready". Any ideas?
Stevex311

Try disconnecting battery for a hour or so and try again. Check engine control fuse to make sure it's not blown,also tap on pcm relay. These may help.

That means they are not functioning well enough to get a reading. You will have to have them checked individually.