[plantchick]

I can't tell you anything about the codes themselves, but the EGR is the Exhaust Gas Recirculation system.

Until someone comes along that actually knows stuff, I thought I'd pass a couple of service manual files along to at least help get you oriented. (haven't gotten around to renaming/sorting these ones yet, so open them in numerical order)

There's a basic description of the system and components, a schematic, and a general diagram of how it relates to the engine.

Tania.