Killing ECU's....

I have a 92 integra with a B16 and I’m having a problem…

The car has sat for quite a few years due to priorities being elsewhere and no time to look at it but back about 5 years ago it had the passenger side floor leak and a lot of water not into the passenger side. The ECU was killed during this but I thought it was becuase water had gotten into it. I bought a new ECU and the car started up and ran for a few minutes before the ECU was killed (big cap blew out same issue as first time).

Fast forward to today I bought a new chipped ECU and had a CEL but the car ran enough to move it from the garage to the side of the driveway and it sat for 2 weeks while our flooring was being redone. I went to start it after that and it turns over but won’t fire up which leads me to think the ECU might have been killed again. This would have happened with the car off but with battery power.

Help me figure out what sensor or circuit has power during key off that would kill the ECU? I don’t even know where to start.

Check for after market wiring that would be the first suspect. Then damaged OEM wiring, especially shorts. Check that the check engine light comes on for a second and goes out on key on. If it does the ecu is fine. The big cap blows a lot in these ECUs.