Empowering Mechanics Troubleshooting EVAP System Leaks with Precision

I have a 2007 v6 and have the check engine light on for [evaporative emission system leak detected (small leak)] , took it to autozone and they told me to ... The way the system determines that there is a large leak is by pressurizing the system and seeing if it holds using the leak detection pump. An EVAP system can have first check to see if the cap is tight and seals against the filler neck. Next remove the cap to inspect the cap O ring seal. The majority of the time I've thought it's to do with EVAP system parts like the charcoal canister, purge valve, lines etc. but just the other ... The evap system is emissions venting for the gas tank. Nothing to do with radiator, AC, or engine vacuum lines. If you see a P0442 DTC, you know there is a fuel vapor leak somewhere in the EVAP system. The small leak code tells you that the leak is probably minor. The first thing to do is to check your gas cap. If the gas cap is not tightly secured, tighten it and drive for a few days to see if the check engine light ... HOW TO FIX EVAP CODES P0455 P0455 P0456 P0457 P0458 P0459 AND LEAN CODES P0171 (LARGE AND SMALL LEAK DETECTED) TOP5AUTOREPAIRS SUBSCRIBE. This code usually indicates a minor problem such as a loose gas cap, damaged vapor lines, a faulty canister purge valve, or a small crack in the fuel tank. The P0455 diagnostic trouble code appears when there's a leak in the Evaporative Emission Control (EVAP) system, and the system can't maintain pressure. The ...