As indicated by the error code P0401, the EGR valve ports were cleaned and gasket was removed and replaced with a new one. How long before or how many miles before the service engine light disappear?
My car has 185000 miles.
My car has an automatic transmission.
The light will not go away until the P0401 code is cleared from memory with a scanner. You should check the two heat resistant hoses that go to the DPFE sensor or the EGR sensor that goes down to the exhaust pipe coming up from the drivers exhaust manifold. These hoses get damaged from the heat from the exhaust over time and should be replaced with the special heat resistance hose. You will then have to have the codes cleared and then the light will go out. If you want to have this taken care of, a mechanic from YourMechanic can come to your home or office diagnose and clear your trouble codes.