zhack44

2001 Toyota 4Runner w/ 3.4L 5VZ-FE 4WD

Currently it's throwing a P0420 and P0446 code. According to FSM the P0420 is a companion code so I've begun diagnosing the P0446.

My gas cap is TOYOTA and clicks properly, already ruled that out. Upon visual inspection the "Air Drain Hose" appears to connect to a metal tube that runs up and reconnects to the filler neck. In my case shortly after the rubber to metal connection the air drain hose is rusted in two. There is also a smaller hose/wire inside of this tube. Knowing that improper pressure differentials can throw this code; could this be my problem?

Thanks

vasinvictor

iTrader: (3)

Yes. Sorry about the rust. I hear it's a real nuisance.

Terrys87

iTrader: (1)

The Fuel Evap System on your generation of truck is easily set off. With your leak in the hose I am sure that is part of the problem.

If I recall right, one of the codes I got was the PO446. Mine was from overfilling my gas tank. I would fill it all the way to the gas cap. When you do that, what you are doing is running fuel into the vent line down to the charcoal canister. I too have an 01 Runner. To fix my Check Engine Light, I replaced my charcoal canister from a boneyard truck. It is located above the spare tire area. It has some Vacuum Valve Switches. At the dealer, the assembly is not cheap.

Some of your problem could be from over filling the tank. Now when the pump shuts off when filling my tank, I might go 50 cents to round it to the next dollar and then no more.

zhack44

Thanks for the feedback, I was aware of the over filling issue. Although I'm hoping that it's not one of my problems it very well could be.

Looks like I'll be moving forward with fixing the hose.