94 protege transmission problems
 

so i bought this car and everything was fine. i let it sit for about a month and started having trans problems. it almost felt like it was slipping really bad. then one day, the car wouldnt move at all when i put it in drive. eventually, i ended up popping the hood, and jumping the box under the hood with the jumper wire. i ended up getting a code 7. problem is, is that code 7 doesnt exist. what could this possibly be?

How much fluid is in the tranny? If its low the trans will slip, if its empty it wont move at all.

tranny had very dark/black fluid in it when i bought the car. i bought it at an auction...shortly after that, i changed the filter/gasket and everything was fine for about 2 months. then the car sat in my driveway for exactly one month and it started acting funny. trans fluid was always full. i drove it for about a week before it wouldnt move anymore. when i put it in drive, it would gradually get going but i didnt have any power. this eventually got worse to the point where it doesnt move anymore. now, i dont have drive, reverse, or anything for that matter. i guess park works, never tried to test it though, the car sits on flat ground.

Check the fluid again for color and smell. If a transmission has been neglected a lot of varnish can be deposited on the wall. After changing the fluid or flushing it the new detergents will loosen the varnish sometimes in larger chunks. This will dirty up the filter right away and it can clog small passages and lead to catastrophic transmission failure.

I am afraid that this could have happened to your transmission. But before you give up, please make sure that all electrical wiring and solenoids work.
I don't know if there is any benefit from doing a second flush or replacement. Maybe, just maybe the new filter got clogged again.
One thing that could possibly work for a while is "Lucas Oil Transmission Fix".