Need Some Advice

[Bigg G]

Our 2001 Avalon with 167,000 miles CEL has came on. The car seems to run fine with the CEL light on with no noticeable performance differences but I'm still curious as to what's triggering the codes. I purchased a cheap OBD2 Scanner and scanned the car for codes and got 5 trouble codes.

P0146
P0441
P0440
P0441
P0446

If I reset/erase the codes the CEL stay off for anywhere's between 300-500 miles before coming back on again.
From the info that I gathered reading in this forum and please feel free to correct me if I'm wrong, it's either a

bad gas cap
cracked Vac Canister hoses
bad Vac Cannister
bad Vac Canister VSV

Are there any other possible faulty culprits ?
Where is the Vac Cannister ?
What & where is the VSV ?


Thanks in advance for your tips & help !!!!!

[Bigg G]

36 looks and not a single response ?????

Should I move this to another thread for anwsers ???

[moonroof]

Originally Posted by Bigg G

36 looks and not a single response ?????

Should I move this to another thread for anwsers ???

I'd give it some more time. Sometimes on weekends this forum can be a bit slow. Not sure why, though.

[pmesfun]

Chill.

First make sure the gas cap is tight.

[HATEnFATE]

When you start getting into codes and culprits, some people will read but choose not to post. Don't worry, be patient and answers will start to show up.

I would also start with the fuel cap. Cheap and easy to replace.

The canister is located right behind the fuel tank and is a black container about the side of a small car battery(even looks like it's make of the same plastic) There is a valve located on it and also a few valves under the hood.

There is also a "vent tube" that is attached to it that looks kinda like the crinkly electrical wire cover stuff you can get. Sometimes those will crack and cause a leak which will kick a CEL.

Start with the cap and work your way up from there.

[bobflood]

Originally Posted by Bigg G

Our 2001 Avalon with 167,000 miles CEL has came on. The car seems to run fine with the CEL light on with no noticeable performance differences but I'm still curious as to what's triggering the codes. I purchased a cheap OBD2 Scanner and scanned the car for codes and got 5 trouble codes.

P0146
P0441
P0440
P0441
P0446

Are there any other possible faulty culprits ?
Where is the Vac Cannister ?
What & where is the VSV ?


Thanks in advance for your tips & help !!!!!

P0146 is a rear O2 sensor code (Bank 1, Sensor 2). If there are two rear sensors, it's the one associate with Bank 1, which is the cylinder bank at the rear of the engine compartment. Probably need a new one.

All the P04xx codes are associated with the EVAP system that captures gas vapors from the fuel tank in a charcoal cannister when the car is not running, then pulls them into the intake to be burned when the engine in on. First think is to replace the gas cap and see if that fixes the problem. Others have pointed out where the cannister is; there are at least two vacuum valves in the system - one on the cannister and another one up on the engine intake manifold. Start at the back - make sure that the vacuum valve on the cannister is working, and that all of the vacuum lines, vacuum connections and electrical connections back there are tight and clean.

Good luck.

[ChiTDI]

Here's one for the P04XX codes.
Code P0446 P0441 P0440 and VSC off
I had this issue and hated all the hoses and wires. Replaced the whole canister assembly/new switching valves/wires/hoses/clamps etc for just over two hundred bucks and have never looked back.
What causes this malady? The canister can be poisoned by overfilling at the gas station. Do you top off? Does somebody else squeeze the extra fuel in to round the cost? Expensive proposition.
Cheap fixes first - gas cap gasket/ switching valves do wear out.
Let us know what you find.