Within the last 18 months I replaced the valley and head gaskets, plugs, wires, and water pump.
The truck is running fine, gas mileage is poor. My wife drives about 6 miles a day and rarely gets above 50 mph. The problem is the CEL is on and will not reset and the exhaust smells really bad(rotten eggs) could this be the catalytic converters? What is the best way to confirm, and what are my best replacement options? Thanks

 

Get the codes read. Then clear them and see what comes back up.

 

i would suspect 02 sensors, which will leak to cat failure if not corrected. Just about any of the big auto store will read your codes for free