Disconnect the battery for 5-7 minutes and try again (sometimes the PCM Keep Alive Memory gets scrambled when battery voltage gets very low).
Check the crankshaft position sensor:
Disconnect the electrical connector and measure the voltage from each pin (harness side, key on engine off) to the negative battery terminal--it should be 1.0 to 2.0V. If not it is likely a wiring problem, though it could mean a bad PCM.
With the connector unplugged check the resistance between the two sensor terminals (key off, engine off)--it should be 250 to 1kΩ. If not the sensor is bad, however this is not a definitive test as the sensor's output could be weak enough to not register with the PCM.
The good news is they don't cost all that much
so while it is not my nature to replace parts and hope I get lucky you may want to just go ahead and replace it...
- 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum, Delta Force tuned,
Steeda UDPs, Ralco flywheel, RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.
New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq