ive got a '89 240, and it used to stall everytime i started it up, either right away, or when i shifted into drive. the engine would rev itself up, and then stall if i didnt give it lots of gas sitting there in park, and flooring it once i shifted into drive, but once but once i got going it was fine. two mechanics couldnt figure it out, so i just dealt with it. finally i found a mechanic who ran it through the computer, and it turned out the air mass meter was bad. that may or may not be your problem, i imagine its worth checking out.
good luck! ~laine