I have an 84 grand marquis and I can't get the doors to unlock with the key. It will turn toward the lock position but not toward the unlock how can I fix this
Try some graphite lock lubrication, or WD-40. Take a peek with a magnifying glass into the keyhole, see if something got jammed in there. If all else fails, remove the door panel and make sure the locking rods are not jammed. There is a rod/lever from each handle to the locking mechanism, as well as one from the door lock actuator. Your car is one the old side, so any number of components could be worn out. The key itself might be worn down. The pins and tumblers in the locks might be worn and unable to turn in one direction. Good luck.
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