['97ventureowner]

After you replaced the gas cap did you have the code cleared? If not the light may eventually go off after awhile if the computer no longer detects a problem. Depending on your driving habits,( how far you drive and frequency,) this may take a few days, or more. You might also want to check the seal on the gas cap. It is possible the new cap could be defective off the auto parts shelf. If the light stays on however, it could mean you have a leak somewhere else in your EVAP system.
Code P1404 is related to the EGR. It can be caused by carbon buildup which prevent the valve from closing. One fix for that would be to remove the EGR valve from the engine and clean any carbon buildup, and clean the passageway into the engine as well. Another "quick fix" is to run an engine cleaner/fuel system cleaner that removes carbon buildup in the engine, but this is only a bandaid fix, as the problem usually reoccurs within a short period of time. Some garages and oil change shops offer a fuel system cleaning service and I have heard that this sometimes works, but like I said the problem can reoccur, and I checked in my area about this service and it costs $79.95. A new EGR valve cost me only $26 more, so I ended up just replacing the valve. It can be a challenge to access the valve as it is located towards the back of the engine on top on the driver's side of the vehicle, so keep this in mind if you decide to remove and attempt to clean the valve and engine passageway. And you should also replace the gasket between the EGR valve and the engine if you decide to go the route of cleaning.