Jeep: 1992 Jeep Cherokee, jeep cherokee, vapor lock

Question
I have a '92 Jeep Cherokee. When I pull out from a dead stop, the engine sputters as if it was experiencing vapor lock. This will last for only a few seconds, then after you get moving it's fine. This problem only occurs when the outside temperature is above 55 deg.F. I've had my local mechanic check the proximity of the gas line to the exhaust, fuel pump,etc. but eveything checked out good. He is as puzzled as I am. I also tried running a tank of hi-test gas, but it didn't help. Anybody got any ideas?

Answer
It's probably time to have the fuel injectors cleaned and not with a bottle of fuel injection cleaner in the gas tank.
It will cost a little but given the age of your Jeep and I would assume the injectors have not been "machine" cleaned, it's probably long over due.  Change the spark plugs at the same time.