Please help with auto tranny

My `88 auto sedan starts out in 3rd gear. I can't get it to downshift by mashing the gas, but 2nd works fine if I put it in 2. I have fresh Honda ATF in there, all solenoids are clean, and I have worked with the kickdown cable. Any ideas? Could this be a TCU fault?

Long version:

For quite a while, she would sometimes shift to third when she shouldn't or she would refuse to downshift. It didn't happen all that often, so I didn't bother with it. This summer after a few hours of high speed driving, I got off the turnpike and when I slowed down a little she dropped into second and the revs shot up. When I drove the car it would drive fine for a few minutes and then suddenly drop into second at highway speeds. I was limited to driving under 50mph. I took it to my mechanic who sent me a tranny shop. The told me it was completely shot and not worth a rebuild. I had asked them to check the solenoids, but they gave up without doing so. I ended up buying a new Saab 92x, but kept my Legend in the driveway. I finally got around to checking the solenoids and sure enough they were crudded up. After cleaning those and then putting in new ATF the car dosen't suddenly drop into second anymore, but now it wont go into second when it is supposed to. The TCU could very well be shot because I had the sunroof leak and dump a ton of water on the floor on a couple occasions. Can anyone suggest anything to try? If I get the tranny fixed up, then I am going to fix a minor dent, replace a cracked head and tail light, get some seat covers and new side mouldings. I would really like to drive this car around again.
Thanks.