93 Mercury Tracer will not shift out of park.

This is probably happening because, underneath your shift console, there is a lever that keeps you from shifting from park without the keys in. The best way I found to fix this was, there are 6 screws, that keep you from getting to it, they are pretty visible, two right in front of the passenger and driver seat, 2 closer to where your feet would be if you were sitting in those seats, and two at the back of the e-brake console. Take this entire plastic off and you'll find that when you sit in your passenger seat, you can see a piece that is most likely dirty from spilled drinks and such, and if you push it, it may not budge, this is a solenoid, this is that piece that is keeping you from shifting from park, I recommend keeping and cleaning the solenoid if your solenoid is not completely corroded, in my case, I had to just destroy the entire thing.

The reason that solenoid piece is why you can't shift from park is because you have that solenoid piece, underneath your shifter, and when you push the button, it's hitting the solenoid. The reason for this is, the fact that your shifter uses a small cylindrical piece to guide and stay in gears, and that small cylindrical piece is probably hitting your solenoid.