The Evaporative system may have problems with the vapor canister releasing charcoal pellets that plug the vent valve. Typically a Code P0441, P0442 and P0446 will be set. The key code is the P0446 which is a vent valve electrical failure. The proper repair is to replace the entire canister with all the valves as a unit. This is located on top of the fuel tank and is expensive. Our Technicians tell us that for awhile Toyota was covering these problems, but this may have changed. It would not hurt to call the dealer if this problem occurs to see if Toyota is still helping with these repairs.Google+
Car Problem Reports
Toyota Avalon Replace EVAP Canister to Correct EVAP System Problems
Toyota Avalon Problem
Average Mileage: 140,769 mi (69,000 mi - 198,232 mi)
Visitor, 1998 Toyota Avalon, 198,232 mi
Check engine light comes and goes and each time I have it looked at its code 0446. I have not took it for repairs yet but plan on it soon
Visitor, 2000 Toyota Avalon, 160,000 mi
I have changed the purge valve,some pipes, and many other things which has cost me about $2000.00., but the problem has not solved.
Visitor, 2006 Toyota Avalon
How do you know if the gas cap is bad 2006 Avalon
Visitor, 1999 Toyota Avalon, 123,000 mi
Too expensive to repair,i just clear the codes and check to see if new codes appear periodically.
Visitor, 2002 Toyota Avalon, 130,000 mi
check engine light refers to po446 evap system
Visitor, 2006 Toyota Avalon, 69,000 mi
While fueling, the pump keeps shuting off as if the tank is full. Diagnosis was the EVAP Canister was stopped up and needed to be replaced.