Toyota Repair: emissions in a 99 seinna

Question
hi my 99 sienna has p0441,p0442 p0446 codes,I cleared the codes and went for inspection ,it failed because the cat-not ready and evap-not ready.I drove around about 180 miles and it still is not ready.the cat and oxy-sensors was changed 5 yrs ago .this vehicle has 244000 miles.do you have any ideas for me as to what is going on and what might need repairing.

Answer
Hello, those codes are for an evap system malfunction, just clearing the codes and not fixing the cause will not let the monitor for the evap system complete, there is most likely a pending code which prevents the system monitor from completing and passing or failing, the most common cause for all three codes are a gross leak, possibly fuel filler cap or a hose off at the canister or under the hood. To force the converter monitor to run start with the car cold then after warm up do a series of acceleration and deceleration drive cycles, the cat may not be getting up to temperature to cause the monitor to run, if it was an aftermarket cat it may be due to be replaced again, if the emission readings were within limits then it is only necessary to get the cat monitor to run and complete and to fix the cause of the evap codes, try first by replacing the gas cap, inspect the fuel filler tube for damage and the evap system hoses, if this doesn't fix it then it will need further testing.