What can cause my car not to go into gear?
Broken wire going to the stoplight switch, or bad switch. It's down under the column. This happend to me twice on my '93, and it was a broken wire both times. I just crimped on a new spade terminal, with a short extension wire that flexes more easily. It's a lockout, you can't get it out of park until you hit the brake, and if the wire's broken, it won't let you. If you can put it in drive, and it won't go, then it's the transmission, could be low on fluid, or shot.
Search Mercury Grand Marquis Questions
Mercury Grand Marquis Experts