Toyota Repair: 1986 toyota mini motor home, engine cranks, mint shape

Question
MR. TED, I HAVE A 1986 TOYOTA MINI MOTOR HOME WITH A 22RE ENGINE, IT HAS BEEN SITTING FOR ABOUT 4 YEARS AND I DRAINED THE FUEL FROM THE TANK  THE ENGINE CRANKS AND IDLES PERFECT BUT AFTER IT WARMS UP AND YOU START TO DRIVE IT IT STARTS SPITTING AND SPURTERING IF YOU LET OFF ON THE PEDDLE IT RUNS FINE, THE FUEL FILTER HAS BEEN REPLACED AND FRESH GAS IN THE TANK AND INJECTOR CLEANER WAS ADDED, THIS THING ONLY HAS 40.000 MILES ON IT AND IT IS IN MINT SHAPE, THE MOTOR RUNS GREAT IDLEING, ONE OTHER THING IS AFTER IT SITS AND YOU CRANK IT UP IT DRIVES FINE UNTILL IT HEATS UP AND THEN IT STARTS THIS SPITTING AND POPING THING, YOU ARE A GREAT EXPERT HOPE YOU CAN HELP, THANK YOU! TIM

Answer
Hello, my first impression is that it is losing fuel pressure, since it sat idle for that long there is a good chance that some rust formed in the tank, most of which may now be stuck in the fuel filter, it's located just under the intake manifold, I would highly recommend replacing it, then let me know the result.