My car ran flawless top swapped with that trans until I stripped the pump (I have no idea how...there's no load on it. OH WELL.) I replaced the pump and it's good, but I got a killer deal on a 5 speed swap so I'm doing that now. It is possible that you have a stuck 1-2 shift valve which does happen to these as well. That is located in the valve body which is in the D/S wheel area under the side cover. Another possibility is a stuck 1-2 accumulator or leaking accumulator seals which is located behind the valve body. You have lots of things to check, and as stated there are other options out there such as a used trans or whatever. Try shifting manually through all the gears a few times without driving. It's possible that there could be some crud blocking a passage. Good luck with it.
