Lets start with the ASD relay. The Engine Computer grounds that terminal 86 at two times. The first is for one second when the ignition switch is turned on. Next, it gets turned on again when the computer sees engine rotation, meaning cranking or running. On older models, it knows that by the presence of signal pulses from the crankshaft position sensor and the camshaft position sensor. Both signals were needed for the engine to start and run. If one signal was lost while running, the engine would stall and not restart.
Around 2002 this changed on some models. You still needed both signals for the engine to start, but if a sensor failed while the engine was running, it would continue to run until it was stopped, then it wouldn't restart. I've never done this myself, but another person posted a similar series of events that you've done with grounding the ASD relay. It sounds like your engine will run in back-up mode on just one sensor, but the computer needs to see both signals to turn on the ASD relay.
There's two observations that will tell if this is correct. The first is the ASD relay should still be turning on for one second when you turn on the ignition switch. If you hear the hum of the fuel pump, that is proof this circuit is working. If you can't hear it or aren't sure, the best test is to measure the voltage at any place 12 volts appears from the ASD relay. That includes any injector, any ignition coil, or either smaller terminal on the back of the alternator. Look for the wire that is the same color at each of those places. That's usually a dark green / orange wire and is shown in the second diagram. A test light is the best choice for this. Most digital meters don't respond fast enough. You should see a bright test light for one second when you turn on the ignition switch. If you do, we're done with the ASD relay circuit. It's working and the computer has control of that relay
Next, observe if the test light turns on when you crank the engine. If it does not, the signal is missing from one of the two sensors. With a failed sensor and an ASD relay not turned on, you'll have no spark, no injector pulses, and no fuel pump. This accounts for about 95 percent of crank / no-starts. What can be misleading is you'll still have normal fuel pressure due to that one second the fuel pump relay turns on each time you turn on the ignition switch.
If the ASD relay does turn on during cranking, (which yours isn't), and you have a no-start condition, it has to be due to a dead ignition system or a dead fuel pump, but not both. Those two systems account for the other five percent of crank / no-starts.
Let me know what you find with these observations. If it looks like a sensor has failed, we're going to need a scanner to see which circuit needs to be diagnosed.
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Friday, August 13th, 2021 AT 8:21 PM