Thought this might help someone who's pulling their hair out over this.
I cleaned under the hood this weekend and ended up troubleshooting a no start situation. Once I got it started ran fine for a while (almost to work) then shut down. I knew it was a water issue but where?! I bought a can of dry air - used for cleaning electronics - and some dielectric grease and starting at the plug wires worked my way round the engine compartment. When I got to the Hypertech PTM it looked fine, but when I sprayed air into the sealing grommet water started to bubble through the pins. I took it apart and sure enough it was filled with water all the way up to the circuit board. Now I know I put most of the water in there myself, but I noticed an area of corrosion on the aluminum that was caused by a smaller puddle of water that must have been sitting there a lot longer. As I tried to find a better way to mount the module I realized there's really no perfect way to mount it because it should be at the highest point of the wiring harness otherwise water will "crawl" into the connector as it runs down the higher wires. Unfortunately the ECM already rightly occupies the preferred position on the wiring harness. I ended up drying the circuit board with air and sealing the grommet with silicon RTV. It seems to have worked.