CEL malfunction?

 I posted a few weeks back about a CEL code 0456 on 00 Concorde. Checked EVAP system hoses, etc & couldn't find a leak. Had a tune up done on car & CEL went off, idling issues stopped & car is running like new. It's been about 10 days since tune up was done. Has Chrysler had issues with diagnostic system spitting out wrong codes or what? I'm pretty certain that the CEL had to do with car needing a tune up & nothing to do with the EVAP system. Does anyone know of any recalls with the OBD?