Did you try the TSB valve fix? Search for F4A-valve or posts by me in a thread started by septicman.
Did you try adjusting the cable that goes between your throddle body and the transmission (tighten it).
I assume that the fluid level is always fine (no major leaks).
Did you try checking the electrical connector on top of the transmission? Sometimes it needs to be cleaned or you can just unplug it and plug it back in.
I assume that your tachometer and cruise control are working (I'm trying to verify the operation of the VSS)
Off hand, I'm thinking that you might have some sort of valve body/solenoid/accumulator problem. Either that or you just plain wore it out. You gas mileage drop to me indicates that it's probably slipping.
Personally I would not drive it like that, except for testing purposes.
If it matters, I think the most miles I've heard of anyone getting out of an ATX here is about 193K.
I've got 180K on mine, and I'm not driving it again until I've done the TSB fix, fluid and filter change, and adjusted the kickdown cable, and I'm probably going to replace my transmission mounts as well.
Lots of of people here often just give up and put in a JY transmission. I wouldn't d that until I was absolutely sure that it wasn't something external that I could fix. If you search there is one person who did rebuilt it themselves, and another person who replaced a solenoid in his valve body.
