Mitsubishi Lancer GT 2.4L P061A and P0507 Codes: Diagnosis and Fix After MAF and Air Filter Changes

My Mitsubishi Lancer GT 2.4L started with a P0401 code, which I resolved by replacing the EGR valve. However, during the repair, I manually opened the throttle body butterfly to clean it—later realizing this was not the correct procedure. After disconnecting the battery on the positive terminal and reconnecting everything, the vehicle initially ran smoothly. But shortly after, the ASC (Advanced Stability Control) service required message appeared along with a P061A code. The car previously had a GTR Stage I performance chip installed via OBD, which was removed multiple times for accessing the check engine light reset function. This history may have contributed to instability in system communication. Initial troubleshooting showed that disconnecting the MAF sensor caused the ASC message to persist but altered idle behavior. It wasn't until we removed the aftermarket cold air intake air filter that RPM increased and the ASC warning disappeared. The next day, after cleaning both the air filter and MAF sensor, the vehicle ran well—but the ASC message returned along with P06 or P0507. I suspected a faulty MAF sensor and replaced it. For about 100 miles, performance was excellent. However, the ASC warning reappeared, accompanied by both P061A and P0507 codes. I then disconnected the negative battery cable for approximately 10 minutes and reconnected—after which the vehicle ran fine again, adding another 100 miles of normal operation. But this morning, the same issues returned: ASC service required and both P061A and P0507 codes. I'm seeking advice on how to properly diagnose and resolve these persistent OBD-II codes in a Mitsubishi Lancer GT with a performance chip history.