2009 mercury mariner 3.0L v6 efi

Question

trying to figure out exactly what the code PO455 on my vehicle

Answer 1

Hi there

This code, P0455 is for a large evap leak. This code can be caused by a loose gas cap so start there. It can also be several other items. You may need to do a smoke test to locate the source of the leak. Sometimes it's the vent control valve sticking open.

P0455 - Evaporative Emission Control System Leak Detected Gross Leak

Read more: https://www.autocodes.com/p0455.html