TBI (not vortec or obd2) crank no start 1995 5.7l auto trans need diagnostic flow chart

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Mater

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does any one have the diagnostic flow chart for the 1995 5.7 TBI?

i have narrowed it down to not getting fuel injector pulse or spark but cranks over fine. i could just toss a pick up module into the distributor but i would like to make sure that is the only issue first.

also found these wiring diagrams but none show the grounds for the PCM (the pickup module grounds in the distributor)
tahoe16.pngtahoe17.png
 
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Mater

Mater

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thanks so far to day this is what i have done figure i should keep a log here in case this get's found in a search

have confirmed the PCM at least has some power and ground as it is able to flash 12 when jumping the aldl connector. the PCM is also able to turn on the fuel pump relay and prime the system the gas tank is also basically empty. still not getting spark or injector pulse so still need to check the pick up coil and the purple wire to the PCM to see if the PCM is receiving the tach signal and actuating the signal correctly with the injector pulse and coil trigger. if the injector and coil fire when grounding out the tach wire then i will know it's the module or pick up in the distributor

after i test the purple wire i wile then disconnect the pick up form the module and power where the pickup plugs into the module with a hot side test light and see if the coil fires when touching it and breaking contact. if it does fire it's the pick up if it does not fire then the module is bad and then i will test the pick up to see if it sends a signal with my multimeter wile cranking to see if it needs a full dizzy or just the module.
 
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putting a conclusion to this

tested the pick up coil resistance got 800ohm witch is with in spec so then took a test light to manually trigger the module by attaching one end to power and grounding the other end on where the pi ck up coil plugs into on the module and nothing. already confirmed it could fire the coil and injectors by grounding out the PCM input

so got a new module and it runs but needs fresh gas as it does run poorly and the fuel flow from the injectors is poor
 

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