Hello,
Just wondering if you found an answer to your problem. I have 96 grand prix 3.1L that does something similar. Runs fine when cool. But when it gets to full hot if it cools down for 20-30 min it will stall after putting it in drive. It spits and sputters, obviously misfiring, in fact the the code reader lists it as a general misfire sometimes. But once it stalls it won't start up again at all until it is completely cooled. Then it fires up just fine. I've tuned it up. Replaced the ignition control module and the coil packs but no help. I'm stumped.
