Manufacture code MOD $11 what does this mean?

P1314-Left Catalyst Damage, Misfire Detected
P1316-Misfire Rate Above Limit
Cylinder numbering begins at the front of the engine.

Check the fuel injector, make sure it's pulsing properly. Check the plugs and wires. Check compression. Compression Should be around 120-150PSI and not vary by 15% from highest to lowest.

PCM Mode Requests:
J1979 (Functional) supports modes $01 thru $0F
†Mode $01 - Request Current Powertrain Diagnostic Data
†Mode $02 - Request Powertrain Freeze Frame Data
†Mode $03 - Request Powertrain Diagnostic Trouble Codes
†Mode $04 - Request to Clear/Reset Diagnostic Trouble Codes
†Mode $05 - Request Oxygen Sensor Monitoring Test Results
†Mode $06 - Request On-Board Monitoring Test Results
†Mode $07 - Request Pending Powertrain Trouble Codes
†Mode $08 - Request Control of On-Board System, Test, or Component
†Mode $09 - Request Vehicle Information
J2190 (Physical) supports modes $10 thru $3F and $80 thru $BF
†Mode $10 - Initiate Diagnostics Operation
†Mode $11 - Request Module Reset
†Mode $12 - Request Diagnostic Freeze Frame Data
†Mode $13 - Request Diagnostic Trouble Code Information
†Mode $14 - Clear Diagnostic Information
†Mode $17 - Request Status of Diagnostic Trouble Codes
†Mode $19 - Request Diagnostic Trouble Codes by Status
†Mode $20 - Return to Normal Mode
†Mode $21 - Request Diagnostic Data
†Mode $22 - Request Diagnostic Data by PID
†Mode $23 - Request Diagnostic Data by Memory Address
†Mode $24 - Request Scaling and Offset / PID
†Mode $25 - Stop Transmitting Requested Data
†Mode $26 - Specifiy Data Rates
†Mode $27 - Security Access Mode
†Mode $28 - Disable Normal Message Transmission
†Mode $29 - Enable Normal Message Transmission
†Mode $2A - Request Diagnostic Data Packets
†Mode $2B - Dynamically Define Data Packet by Single Data Offsets
†Mode $2C - Dynamically Define Diagnostic Data Packet
†Mode $2F - Input/Output Control by PID
†Mode $30 - Input/Output Control by Data Value ID
†Mode $31 - Enter/Start Diagnostic Routine by Test Number
†Mode $32 - Exit/Stop Diagnostic Routine by Test Number
†Mode $33 - Request Diagnostic Routine Results by Test Number
†Mode $34 - Request Download - tool to module
†Mode $35 - Request Upload - module to tool
†Mode $36 - Block Transfer Message
†Mode $37 - Request Data Transfer Exit
†Mode $38 - Enter Diagnostic Routine by Address
†Mode $39 - Exit Diagnostic Routine by Address
†Mode $3A - Request Diagnostic Routine Results
†Mode $3B - Write Data Block

More then likely this was one of two things that happened. First you had a loose connection at the coil and when you plugged it back in, it made a better connection. Second the plug was fouled and when you cleaned it, it started firing stronger. If this starts again, I would change the plugs and see if it clears up again. However, whatever you do, I would only do one thing at a time so that you know if that was the issue rather then not knowing what caused the change.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Let us know if you have other questions. Thanks