It's been a while since I was here but I found this service bulletin:
Ignition Key Cannot Be Inserted, Rotated, or Removed from the Ignition Lock Cylinder
Step
Action
Yes
No
1
Ensure the transmission shift lever is in the PARK position and the steering column is NOT in the locked position.
Verify the ignition key cannot be removed from the ignition lock cylinder.
Can the ignition key be removed from the ignition lock cylinder?
Yes - Go to Step 4
No - Go to Step 2
2
Verify the ignition key cannot be turned to the OFF position.
Can the ignition key be turned to the OFF position?
Yes - Go to Step 3
No - Go to Step 7
3
Verify the ignition key cannot be removed from the ignition lock cylinder.
Can the ignition key be removed from the ignition lock cylinder?
Yes - Go to Step 7
No - Go to Step 12
4
Verify the ignition key cannot be fully inserted and rotated without sticking in any position.
Can the ignition key be fully inserted into the ignition lock cylinder and be rotated without sticking in any position?
Yes - Go to Step 7
No - Go to Step 5
5
Inspect for an incorrect, worn, or damaged ignition key.
Is the ignition key incorrect, worn, or damaged?
Yes - Go to Step 10
No - Go to Step 6
6
Inspect the ignition key. Clean the entire middle groove area of the side milled ignition key.
Can the cleaned key be fully inserted into the ignition lock cylinder and be rotated without sticking in any position?
Yes - Go to Step 13
No - Go to Step 12
7
Verify the adjustment of the shift control cable. Refer to Range Selector Lever Cable Adjustment.
Can the ignition key be turned to the OFF position and be removed?
Yes - Go to Step 13
No - Go to Step 8
8
Attempt to override the ignition lock solenoid on the ignition and start switch housing.
Can the ignition key be turned to the OFF position and be removed?
Yes - Go to Step 9
No - Go to Step 12
9
Inspect the electrical system for improper operation. Refer to Ignition Can/Cannot Be Turned Off with Transmission in Any Gear and to Testing for Intermittent Conditions and Poor Connections.
Can the ignition key be turned to the OFF position and be removed?
Yes - Go to Step 13
No - Go to Step 11
10
Replace the ignition key. Refer to Adding Keys.
Did you complete the repair?
Yes - Go to Step 13
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11
Replace the floor shifter. Refer to Automatic Transmission Range Selector Lever Replacement.
Did you complete the repair?
Yes - Go to Step 13
--
12
Replace the ignition lock cylinder. Refer to Ignition Lock Cylinder Replacement.
Did you complete the repair?
Yes - Go to Step 13
--
13
Operate the system in order to verify the repair.
Did you correct the condition?
System OK ----- (hopefully

)
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