Hello, the fact that you can't remove the key is related to the not staying in park. The key can't be removed unless the transmission is locked in park. There are a few possible reasons for this. The first thing you need to do is look at the linkage on the side of the transmission and watch it turn while some one else works the shift linkage. You will be looking to see if the problem is inside the transmission or in the linkage going to it. If you unhook the cable from the side of the transmission and can put the transmission in park manually, then you know the problem is with the cable or the shifter assembly. If it is inside the transmission, the oil pan will need to come off to be inspected. Chances are pretty good the problem is in the shifter or the lock out solenoid for the ignition key. To look at this, you will need to remove the console. There has also been some problems with the rubber boot binding the shifter up so it can't lock in park. That will be the last thing in the post for you to read. Inspect the shift assembly for bent or loose parts that keep it from locking in park. It may just need the cable adjusted and if it looks like that is the case drop me a note and I will send you instructions. You will also want to inspect the park lock solenoid and linkage to make sure it is not loose, bent or broken. If you have problems let me know. The first post below is a list of the causes inside the transmission that would keep it from going into park. the last one is the bulletin on the shifter boot. Keep me informed. Thanks
Parking Lock Actuator Linkage (85-90)
This bulletin is being revised to include the 2008 model year. Please discard Corporate Bulletin Number 05-07-30-021A (Section 07 - Transmission/Transaxle).
Some customers may comment that they are unable to remove the ignition key from the ignition cylinder.
The shifter boot may be caught/trapped in the shifter assembly mechanism.
DON'T DO THIS
Reposition the shifter boot.
DO NOT replace the complete shifter assembly.
ONLY replace the shifter boot if damaged.