1996chevy1500

I would have the truck scaned. That would tell you where the problem is. You can try to use some throttle body cleaner and clean the throttle body. Sometimes a little carbon gets in there and will mess around with the idle air control or the throttle positionion sensor. Make sure if you use the throttle body cleaner follow the instruction. I have seen a little carbon mess up how a vehicle starts and runs. If that does not do the thing then get the truck scanned.