Straight out of the shop manual: "The automatic shut down (ASD) and fuel pump
relays are mounted externally, but turned on and off
by the powertrain control module through the same
circuit.
The camshaft and crankshaft signals are sent to the
powertrain control module. If the PCM does not receive
both signals within approximately one second of
engine cranking, it deactivates the ASD and fuel
pump relays. When these relays are deactivated,
power is shut off to the fuel injectors, ignition coils,
fuel pump and the heating element in each oxygen
sensor.
14 - 28 FUEL INJECTION"”SYSTEM OPERATION"
When I jumped the relay coils (turned them on) I heard the both the realys turn on and I could hear the fuel pump come on, but still no spark. The PCM is obviously not turning this stuff on for a reason. Probably one of those 2 sensors.
Wait! New information.
Nevermind. I bet both sensors are fine. I checked the voltages at the sensors and got 100mV at the two sensors' reference voltage wire. This is supposed to be 8V.
Now this is again straight out of the manual:
"The PCM contains a voltage converter that changes
battery voltage to a regulated 8.0 volts. The 8.0 volts
power the camshaft position sensor, crankshaft position
sensor and vehicle speed sensor. The PCM also
provides a 5.0 volts supply for the engine coolant
temperature sensor, intake air temperature sensor,
manifold absolute pressure sensor and throttle position
sensor."
Bet the "voltage converter" isnt doing its job. Bad PCM. (These PCMs are known to be very cheap and junky). Then again maybe the corrosion in the wires is causing a voltage drop resulting in less than a volt at the sensors. Hmmmmm. Now im finally getting somewhere
Friday, October 9th, 2009 AT 7:57 PM