'96 buick park avenue starting problems

for the past several months we have been having starting problems with the '96 park avenue. At first we found that just waiting for the security light to go of (usually about 3 min.) would do the trick--the car would start. Recently, it has been necessary to put the car in gear back and forth to get it started. Today, that isn't even working. My husband cannot find any wiring information for the security stuff--he has looked in the Haines (?) book etc. He loves cars and is very mechanical and would appreciate any help or ideas someone might have!

does it turn over and tries to start or do you get nothing at all could be cps located behind crank pulley. did you clean battery cables. do you get a spark from plug wire to coil? did you try different key,

does it turn over and tries to start or do you get nothing at all could be cps located behind crank pulley. did you clean battery cables. do you get a spark from plug wire to coil? did you try different key,
It does not turn over at all. Have done all the above--but wondering what is the cps?

cps is the crank positioning sensor

i have the same problem in my 89 park avenue ultra. I input the key into the ignition, and i cant turn the key forward to start the car or backward to put on the radio.
wat can i do ?