OBDII code P0446 EVAP vent control circuit malf

Corolla 2002 54K mile auto, no symptom and sign, MIL on.

What is that VENT mean here ? any idea for the defect part(s) and repaire

cost ?

Can my neighborhood mechanic fix it or need to bring to dealer ? Thx !

You certainly don’t need a dealer. How ambitious are you? Its not all that difficult to mess with if you have a few simple things like wrenches and multimeter. Your neighborhood mechanic can easily handle it.

The evap system collects the gas fumes from your tank and sends them through a set of vacuum lines to the engine to be burned in the engine. I don’t know the Corolla’s system, in particular, but there is a purge valve and probably electronic solenoid that opens up the vacuum lines to allow the fumes to be sucked in. If the computer doesn’t detect activity from the solenoid/valve it will set a code like this. Check this out:

The solenoids & valves can be a bit pricey, but are usually not hard to change.

The first thing I would do is have the codes cleared and drive for a while to see if it comes back.

A little black tape over the light makes this “problem” go away… To fix it “the right way” can as simple as replacing the filler cap or spotting a split or disconnected vacuum hose or it can turn into a nightmare fishing expedition hoping the last expensive part was the right one…All this to make the EPA happy? Your car could not care less about it…

Unfortunately cars with CELs lit don’t pass inspection.

Or notify the owners when something really serious begins to go wrong.

The most common cause for this is chronic overfilling of the gas tank. If you stop filling the tank the first time the handle clicks off, the light will go out on its own in a few days. The code will clear from the computer in a couple of weeks.

If it’s REALLY serious, you WILL be notified…:slight_smile: No CEL needed…