||Fuel filter: replace, fuel pressure: check, Spark plugs: Common after long time parked: Replace. Fuel old: drain and replace, air cleaner check, plugged or full muffler or exhaust (mice, etc)Disconect at or before muffler and test drive. Cataltic converter plugged: have back pressure checked, Camshaft worn out or damaged, common failure on engines that sit for long periods: Remove valve covers and measure lift.
The exauhst is easy if you get someone to follow you and listen to the tail pipes, should hear rumble until high throttle: 60 mph or less cruise for example. If it sound like a plugged hoover at low speed, thats probably your issue.