Persistent P2421 and P2422 Codes
I have a 2007 S550 that for the last year has had The P2421 and P2422 Codes.
I have replaced both evap valves (under the hood and on the Charcoal Canister)as well as the fuel cap which got rid of the codes for about 1K miles but the ultimately came back. I do not have fueling issues as it is indicating that the valves are stuck open.
I have a replacement canister that is scheduled to be delivered tomorrow.
I am just wondering if there is anything else I should be checking, or if anything else could be the problem.
Thanks in advance






