This is a crank no start situation. I have tried everything and replaced about everything! I have had intermittent spark. The truck started one time when I was prodding the #5 wire on module with a tester. It ran great and died after about 10 miles and would not start back up. Does anyone have any suggestions? We took the distributor out one time and sat it on top of engine, where it was grounded, and turned gear on distributor. We had a test light hooked up and it pulsated like the distributor was working fine. However, truck would not start when we put it back!
I doubt you have tried everything and without a wiring diagram it will be impossible to know what "everything" is.
The timing signal must come from somewhere, to be processed by the engine management ECU into pulses for the fuel injectors and the ignition amplifier. The timing signal generally is from the distributor or crankshaft position sensor and there could also be a camshaft sensor involved too.
An oscilloscope is the best method for testing and tracing such signals and pulses but much can be done with a multimeter, though neither analogue or digital will be fast enough to record either the input signals to the ECU or the output pulses so the ohm meter will be the main tool.
Noid lights can check if the injectors are receiving a pulse and if they are you can be fairly confident the ECU has a good supply and ground and input from the crank sensor though it can't be taken for granted the ECU is sending a pulse to the ignition amplifier but with the aid of a wiring diagram the wiring and supply and ground of the amplifier can be checked but without the aid of an oscilloscope no firm diagnosis can be made though the balance of probability would say the ignition amplifier is less long lasting and reliable than the ECU.
It is also worth a mention that the current flowing in some of those connections is very small and so such as the ECU and ignition amplifier connecting pins must be spotlessly clean. I have known some of them to develop a virtually invisible oxide coating and that is enough to prevent the engine being started - if any of the pins appears less than bright metal it would be wise to clean it and the receptacle.
I hope this helps.
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