see this link for an explanation of all problems.
any help would be great..i think it's electrical problem, not trans, and that the IC circuit is either open or shorted...not sure how to test or repair.
while driving or slowing down toward a stop, my 1992 SL2 will downshift hard making the saTurn buck/jerk, the service engine (SES) light will turn on and "shift to d2 light" will flash on and turn off, or it will stay on...if it stays on the saTurn then will drive sluggish and slow and barely accelerate. used to happen once a week now it happens every 20 minutes or so...sometimes the downshift feels like you another car just ran into you. damn..quite the eye opener in the morning .. after driving sluggish, if you turn off the 'Turn and turn it back on again, it won't drive sluggish until the next erratic shift.. btw, it has about 105k miles and automatic transmission