note that on some models and years such as our 98 achieva you simply just cut the yellow wire at the ignition key switch and that does it, but the security light will remain lit permanently
i did this to our car last fall and it has been perfect ever since
we tried having the IPC repaired twice at the place in virginia at 200 bucks each time, and the dealer tried twice to fix this issue and all to no avail at 500 bucks a visit
cutting the wire is what was the last resort and works
also have had problems with the key and shifter interlock even after a brand new shifter assembly from the dealer
so i removed the solenoid deal at the ignition key switch in the column
took care of that issue as well
now the key will always turn off and come out
some of the mid to late 90's cars are not repairable the correct way
grand am
achieva
and so on
good luck