I have an 88 S10 Blazer, 2.8 automatic that is doing something I have never seen or heard of before. When you start it, it runs perfect on the road until the motor warms up. Once it warms up, it's like the transmission starts slipping. You can stop and shut off the engine, count to 10 and start it up and it will jerk your head off and run perfect again for a few minutes. After a few minutes it starts the same thing over again. As long as you stop and shut the motor off for a few seconds it will start up and run perfect again for a few minutes. There doesn't seem to be any problem with the motor. What can it be? I would appreciate any help. Thanks.