Post #3 on this page-
You are either not getting a valid crankshaft position sensor signal, or camshaft position sensor signal, and the PCM is de-energizing the ASD relay.
ENGINE START-UP MODE
This is an OPEN LOOP mode. The following
actions occur when the starter motor is engaged.
If the PCM receives the camshaft position sensor
and crankshaft position sensor signals, it energizes
the ASD relay and fuel pump relay. These relays supply battery voltage to the fuel pump, fuel injectors,
ignition coil, and oxygen sensor heating element. If
the PCM does not receive the camshaft position sensor and crankshaft position sensor signals within
approximately one second, it de-energizes the ASD
relay and fuel pump relay.
The PCM energizes all injectors until it determines
crankshaft position from the camshaft position sensor and crankshaft position sensor signals. The PCM
determines crankshaft position within 1 engine revolution.
After determining crankshaft position, the PCM
begins energizing the injectors in sequence. The PCM
adjusts injector pulse width and controls injector synchronization by turning the individual ground paths
to the injectors On and Off.
You are either not getting a valid crankshaft position sensor signal, or camshaft position sensor signal, and the PCM is de-energizing the ASD relay.