Volvo xc70 code po456


My volvo xc70 check engine light came on. My mechanic ran a diagnostic and found code po456 small evaporative leak but he could not find any leak. He cleared the code but the code came back 2 months later. Any idea what’s the problem? Do I have to take it to the dealer?


Possible loose gas cap, though I more regularly see P0440 get thrown by this. Its possible that it is a different code this time.


Odds are the gas cap is loose or not sealing properly. Outside chance of a leak in one of the evap lines.


Thanks for your quick reply. I have in fact put on a new gas cap but the code hasn’t gone away.


Smoke machine is the best tool to find evap leaks…failing purge valve,charcoal canister,hoses must be checked leaks…