evaporation system readiness failed
If you have one of the older 4th gen fbodies it may be inside the left-rear quarter pannel; take out one screw and part of the inner fenderwell linner comes out.
It's a 98 so if its the canister or vent valve, hopefully it's in the quarter panel.
https://ls1tech.com/threads/showflat...31&fpart=1


