I had an issue years ago back when I had the L36 (3800 Series 2 N/A) engine in my car where it would start shutting off if it was raining. Found that water was getting into the crank sensor connector and this was shorting out the output signal enough that it would shut the engine down. I couldn't find anything in particular wrong with the connector seal or connector itself, so I just stuffed the crank sensor side of the connector full of dielectric grease and plugged it back in. Never had a problem after that.
Check your crank sensor connector, ignition module connector, and ignition wiring harness to main PCM harness connectors for water/moisture. If any is found, check to make sure the seals for these connectors are good. IF not, replace them. If so, try packing them full of dielectric grease and see if that fixes it. Wouldn't hurt to check all the other electrical connectors on the PCM harness to make sure they are all dry.
OVERKILL IS UNDERRATED
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