1988 Chevy Truck cold starting

first start of day engine stumbles for about 2 to 5 seconds and then quits and after 7 or 8 of the same type of attempts (also will not throttle up on any of the attempts). Then the engine starts, Idles and accelerates normally. I have replaced o2 sensor, throttle positioning sensor, idle air solenoid, wires and plugs and cap changed about 5000 mi ago. This happens most often when the truck sits for more than 12 hours or so.