Crank, no start, no rpm signal, help

[We-R-138]

Alright guys, this has been driving me up the wall here and I thought I?d bring in a little help.
Quick back story?I?m a 21 year veteran in the automotive repair industry, owned a repair shop early in my career for 6 years then switched to restorations and customization/swaps, that sort of thing, closed my shop during the pandemic and have been building personal cars from my home shop full time since then and i do EVERYTHING myself, metal shaping, rust repair, interior, glass, engine buildin, machining (manual only), body, paint, chassis, and electronics.
So I know my way around a swap, and can build pretty much anything. BUTTTTTTT this thing has me completely stumped and it?s driving me absolutely crazy.
Okay, so vehicle is a 1993 GMC s15 Jimmy 4x4, has a 5.3 swap w/ heads, cam, custom stainless single exit exhaust, built 4l60e 2wd conversion (2wd?s are hard to come by in my area and this one was OUTSTANDING condition so I caved and went the route I did. OG PAINT is immaculate interior is like no one had ever even sat on it, etc. ),

Anyways, the story?.
Get the truck running, start doing my tuning thing, getting some miles on it, runs great, no issues, and the other night, pulling up to a pizza joint, sputter sputter sputter dies. Won?t restart. Have my laptop w/vcm scanner so I take a look see what is going on, and I have a p0335 (crank sensor circuit malfunction) run home, grab one out of another 5.3 I have laying around, pop it in, and fired up, drive home great. No issues. I?m thinking cool, I?m going to hit the cars and coffee in the morning in Lake Tahoe. Go to fire it up. Crank crank crank no fire. No rpm signal, check for signal with an oscilloscope, i have pulse, but no 12v signal coming from the pcm, double checked all my grounds, connections, fuses, even popped in another pcm I had for another project (gm 0411 dbc return fuel rails). Nada, nuthin, just cranks. I put power to the 12v ignition wire #2 on blue connector with a power probe, fuel pump lights off, and injectors fire (checked with noid light) but no coil fire. I have checked depth on the sensor, deeper, shallower, doesn?t matter, even ran temp hot leads to the stand alone harness relays and fuse panel, nuthin.

So I?m stumped. Any help would be astronomically appreciated and grateful.

[edcmat-l1]

Jeezus can we get a summary? And where's the data log and any other pertinent real technical info to go along with the way too long story?

[We-R-138]

Okay, no start but cranks, no 12v signal out of the pcm @ pin 2 blue, checked and remounted all grounds, have all power connections to pcm full battery voltage and ignition switched pins (can?t remember off top of my head exactly which ones) 1993 gmc s15 jimmy with stand alone 0411 dbc built-ish 5.3, 243 heads, comp cams xr series cam. Truck ran, then quit, put in new crank position due to the p0335 in a parking lot, got it home, and cranks but now no start since. Injector and coil grounds good, no positive at coils as well.

No rpm signal from crank position, 12v reference, good ground at sensor.

I can try and get log but there everything but rpm is up to snuff. Just dead flat at zero.

[gtstorey]

Do you pro's remember all of the pinouts for all of the ECM connectors? Does pin 2 Blue mean anything to you without the wiring diagram? For myself I would need a wiring diagram for that to mean anything.

Have you tried to start it with flammable spray? But it won't start without an rpm signal. Not sure what "rpm is up to snuff. Just dead flat at zero." means if the rpm is zero when the rpm isn't actually zero.