When starting after sitting more than 1hr, the car will not start properly. The only consistent way to make it start is to manually open the air flow meter door (potentiometer, not a sensor), crank it, it then dies, let AFM door close, then crank and it starts. Presumably, the AFM door is making the injectors fire additional fluid vs the amount of air, but I can't figure out why it doesn't do it automatically. This is likely going to require specialized knowledge of this type of vehicle.
What've I've done/confirmed:
-Car runs great after starting (short trips, long trips, you name it, it can do it)
-Replaced AFM
-Don't appear to be any fuel pump/filter issues (pressure in rail is 36psi as spec, no stalling issues driving up hills/under load, etc.)
-Injectors fire
-Many vacuum hoses/ports replaced/sealed
-No evidence of ECU failure since it runs great otherwise
-CSI not relevant due to ambient temperature
-timing is correct
-replaced air pressure regulator
-Priming rail does not help
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Rubber air duct in GOOD shape? .. Cranking engine is what moves the air vane - air vane movement is what triggers fuel pump - any leak in the air duct tube will result in extended cranking / no start.
Otherwise *hands-on* testing by qualified personnel will be required.
Close examination of the air tube may reveal cracks caused by air filter replacement.