korelabs

was taking my dog to the vet monday afternoon, truck was running beautifully as usual, slowed down to stop at a red, and it just turned off. no thump, no shudder, no stutters, nothing, it was as if I had turned the key off, 255K miles, one rebuild about 100K ago and this is the *only* issue it's ever had, man can this thing pick em though.

Finally towed it home, the button inside the cap was completely scorched out of it, and the housing blackened, found button and spring sitting in the top of the now soot blackened rotor.

I have changed:
new plugs
new wires
new fuel pump
new fuel filter
new cap
new rotor
new coil
new ICM (old one tested fine, I hate taking chances)

What I have tested:
tbi sprays one good burst while pump primes, then alternates back and forth as trying to crank, as it's supposed to do.
stator output is .788v AC, within the .3 to 1.8 tolerances when cranking.

tested new ICM before it left store, then had 2 other stores test it to be
safe.

5A ignition fuse is fine.

coil does receive 12V DC when key is on.
coil however does not put spark out.

I'm lost on this...

Cap pic:


Rotor: little blurry, sorry.

MDTAHOE

Sounds like the pick up coil is bad. Use a test light to check for the negative trigger from the pick up coil to the ignition coil. Hook test light to negative battery cable check for power to the coil when key is on (sounds like you already did).Now hook test light to positive battery cable and probe the other wire on the ignition coil, crank the truck the test light should flash. If it does not replace the distributer as an assembly. You could take it apart and replace just the pick up coil but based on the age replacing the assembly makes more sense.

korelabs

Where is that located? all this model has is the ICM and stator inside the cap and both of those tested fine, I know in the older HEI's they had the hall pickup in there, but this one's the external coil and i cannot for the life of me find that stinkin pickup, that was my very first thought as soon as it died, but again, can't find the sucker in there, thought they had incorporated it into the ICM somehow.

MDTAHOE

it is inside the distributor, you must completely dis assemble it. Remove the gear from the bottom and pull out the shaft. You can not miss it

1993 Chevrolet Truck Pick Up Coil Problem Distributor Remove Replace Pickup...

1993 Chevrolet Silverado Pick Up Coil Problem Mechanic 93 Chevy Truck V6...

korelabs

Only thing in there I saw was this guy, and it tested ok, did I miss something?

MDTAHOE

You need to check the signals at the coil. If both are present and you have no spark your new coil is bad. Nothing else matters until you do the above test. Regardless of how the above part "tested". Ohm the wires from the dis to the coil it is possible one is broken in the wire jacket

korelabs

Understood, and thank you for the clarification, I was about to go pull the battery off the charger (flattened it trying to crank the monster), could I use a test light (incandescent, I don't have an LED model)? or a multimeter to check for fluctuations as I'm not entirely sure how to ohm something? was also gonna see if it codes on me with a fresh charge.

Followed this guide to get as far as I have, I'm guessing I test connector "1 A"?
http://easyautodiagnostics.com/gm_ic...n_module_2.php

MDTAHOE

A non led test light would be the best choice. There is no point in testing the ICM as you have put 3 in, it is not the problem. If you have no negative trigger to the coil you need a distributer. Extremely common

korelabs

After replacing everything i could think of, including pulling the distributor and changing that pain in the butt stator, and it STILL didn't start, I threw in the towel, and at 2am, called my dad back home in PA who's been working on these things since before my time... he said "change the fuel pump relay"... it worked.

no idea why or how, it was getting fuel, the pump was running, pressure was fine, I got no codes, but replaced the relay and it fired the second current hit the starter. How the hell does that work? lol thank you for the help, I'll definitely be sticking around this place for a while!

kevinkpk

That is the pickup coil, did you remove it? If not, you need to pullit, and inspect the whole thing for insulation being intact, they are a pita!