boatguy57

I have a P0440 code that is reoccurring after reset. Any insight on what is going on would be appreciated

mdbrown

Good news: It won't affect driveability, safety, or longterm health of your vehicle at all. Bad news: it can be a pain in the butt to find the source of the code.

The 0440 code is a evap emission system malfunction. Typically it will pop up after a fillup. Candidates for the cause could be loose or leaking gas cap, purge valve failure, evap cannister blockage, a split/disconnect hose somewhere in the evap system or evap pump failure.

Quick description: periodically (when certain conditions are met) the system will pressurize the fuel system then look for a pressure drop, if it detects less than proper pressure you'll get that code. The system is meant to collect fuel vapors from the gas tank and route them back through the engine to be burned. It has a fair amount of rubber line, a purge pump, a purge valve and the charcoal cannister. Shops have a smoke machine, they pump the system up with smoke and look for leaks and they'll test the gas cap. If you have emissions testing where you are it will have to be fixed prior to, if not it's a minor issue. All you can really do is make sure the gas cap is tight and do a visual inspection for disconnected/cracked/broken hoses. Anything more will require a shop.