I have a JDM P08 factory manual ecu.
Socketed by someone else and ran in customers car fine for a few months. Then random CEL's started when driving which bought up codes that didn't exist.
I then resoldered the socket and latch plus checked over everything. Main cap has been replaced.
ECU Passes on my moates engine Sim and primed the fuel pump, hits vtec, NO CEL.
Put ECU in the car and it primes the fuel pump but SOLID CEL. Car starts and runs in limp mode.
I removed J1 and put ecu back to stock. Primes fuel pump and SOLID CEL STILL!
When key turns on, fuel relay primes and CEL comes on. Relay clicks off and CEL remains on SOLID (like there is a chipping issue but J1 is removed now)
What inside the ecu can cause this? visually everything looks ok.