No crank/heatsoak issue

[Eurocopter]

Guys my 1997 burb k2500 quit while driving home from a refusal to pay $2300. For brake work. Suspect! I have no spark. I hear fuel pump run when key turned. I replaced ignition module and coil, no luck, I changed fuel pump relay, no change. Last attempt to start with key did nothing at all. The door open tone but no dash lights, no start, nothing... I'm guessing some sort of a ground fault situation that would occur after driving and hitting bumps in road. If it was a set up from shady shop I can't figure out the intentional fault or how you'd get it to run for 20 minutes then quit and not start again. We just drove it to Miami and drove around for 4 days and then back home (over 1200 miles)
Already replaced plugs, wires, distributor cap etc at 116k miles. Now at 118,500 and this issue after it being at shady shop. Anybody have any knowledge of how to purposely cause problems like this? I can't see anything out of the ordinary... I may be wrong and the problem may be natural even though the timing of the issue is strange!

 

[Eurocopter]

Of note; a fella at the desk at shady shop stated he needed to go get mileage, opened door, released hood, walked to hood, opened it all the way, then closed hood and came back to desk. I asked how opening the hood could have anything to do with mileage and he stated I like to make sure everything is okay. I couldn't see him do anything, but that was strange...

 

[Schurkey]

Verify fuel pressure. Use a spark-tester calibrated for HEI to verify spark.

Are ALL of the fuses good?

 

[Eurocopter]

Verify fuel pressure. Use a spark-tester calibrated for HEI to verify spark.

Are ALL of the fuses good?

Okay, I got it. Crankshaft position sensor went bad. Seems suspect, the timing was crazy! $80. 5 minutes.
For what it's worth; I learned you reset ecu by disconnecting battery for 5 minutes. I also learned if the tachometer doesn't move when cranking engine it is the Crankshaft position sensor. Pretty simple...

 

[thinger2]

For quite some time, I've had an issue where in summer, with regular on/off driving and traffic, I've turned my truck off and it hasn't started again for a while. In the past I've normally had to wait 1-2 hours before it will crank. Dash lights come up but no crank at all. For the longest time, I thought is was the oil pressure sender at the back of the block, (fuel/oil) as I used to have my guage reading faulty. I've replaced that with an ac delco one some time ago and it reads fine, but now the trucks started doing it again. No codes come up. Is it more likely to be a starter solenoid, or something like ICM, coil etc? Being that it only happens when the engine bay temp gets up makes me think it could be some kind of electrical heatsoak. She's a 350 Tbi
Cheers.

 

[Eurocopter]

I'm just learning about these issues, from what I've read that sounds like a bad coil, they get a break, but doesn't expand/seperate until it heats up then it has to cool down to function again...
IMHO the coil is a cheap thing to try and it couldn't hurt to have a new one...it wasn't my problem but the coil and the ignition control module I changed... mine seems to run smoother...
Also note from above; is your tachometer needle moving when you turn engine over?

 

[Schurkey]

Or wait until the coil heats up, and car stalls, then TEST the coil with an ohmmeter to verify broken wire(s) and/or shorted windings.

 

[Tpok454]

@Schurkthank you for the very informative post. I will definitely perform a VD test and if under voltage check the purple wire to the S terminal and check it back through the harness. Very much appreciated for your help!

Did you ever figure out what the issue was?