Fuel pump relay- the "Tach needle bounce test " would eliminate that easily. The CPS ohm test would confirm.
Smart suggestion because it is easy to fit the spare relay (oddball style pins)for the fuel pump that you always carry !or the diy jumper cable to bypass the relay
996-615-101-00, Note the small 5th pin. No Auto Parts store in the Boonies has that !
Pelican Parts
Boxster cranks but does not start