1986.5 Auto tranny problem

[CiDirkona]

I have an 1986.5 Supra which will shift through the gears as soon as you push down the accellerator, leaving you to lug everywhere in 4th (or 3rd with o/d off). I can still change gears via the shift lever and o/d buttons if I need a little bit more acceleration, but it's really annoying. She doesn't downshift with kick-down either. I took it to a tranny shop, they said the kick-down cable and fluids are good, but it'd cost money to get more of an inspection...

I'm not pulling any ECT codes, but I am pulling ENG code 11.

I was also conemplating getting that auto-tranny shifter doo-hickey from suprasport.com, but at $400, that's quite an expense if it wouldn't even fix my problem. Does anyone have the schematics for it so I can make one myself (I know my way around ICs and soldering irons, but don't know enough about how the solenoids work. I could make a sequential circuit to flip the solenoids, but wouldn't quite get the shift protection thingo right).

Does anyone know how to fix this? I saw someone get a fix for it on automotiveforums.com, but they didn't say HOW they fixed it (and annoyed the crap out of me at the same time).

Thank you!!!
-Colin cidirkona@yahoo.com