Truck will run but kills when put in gear

I have 98 tahoe, w/ 5.7 350. About 5 months ago I was driving up the road and it just killed( did this twice that day). Put it in neutral started back up and I kept rolling. A month later it killed on me again but would not restart. Got it towed home and it started 2 days later. At this point found out I had a blown headgasket. Got it fixed and drove the truck for about 4-5 weeks to break it back in. Because of my distance I started to drive daily I switched back to my car. So now truck has sat for about 4 weeks and decide to get in and go a few places. On my last stop, I came out and started it up and drive off. After about 2 blocks it kills and won't start back up. Pulled it home, checked the usual, fire, gas, and everything plugged in. Found it had intermittent spark so I changed the distributor cap and she started but would't run. If I play with the gas I can get it to stay running. But once I try to put it in gear, it kills. Only one code came up and that was P0101. Everything is plugged in and I can hear some air. Even changed the mass flow sensor and still the same. Had someone check it out end they said change the injectors since it would fluctuate when started. I'm like if it will run, it can't be the injectors and from what I've read it sound more like the crank position sensor. Any sensible advice is greatly appreciated.

the cranksensors usually act up when heated. I have had some when heated go to high resistance/open . then you get no signal.

since its this old just replace it. make sure its mounted correctly and the connector/wires are good.

next remove the ICM inside the distributor base. go to a autozone that has a wells module tester and get this tested ,these also act up like this at this age.