Mitsubishis have a problem that, sometimes, after the engine has been worked on, the “non-continuous readiness Monitors” won’t set to Complete. On a scan tool, some of the little monitor ovals will continue to blink, which indicates this “incomplete” or “not run” status.
Mitsubishi has put out a Technical Service Bulletin, TSB-04-13-012, dated December 2004, New OBD II Drive Cycle Patterns, which should be done to get the readiness monitors to set.
This older TSB has a fuller explanation of what condition the TSB is for: http://www…ycles.html
Where is the Car Tips sections, here at Car Talk? A dedicated TIPS SECTION is where this tip needs to be.
The newer Mitsubishi Technical Service Bulletin, TSB-04-13-012, is the one to follow to set the Monitors. The other TSB is just background information.