Question for Lexus experts, please help.

My 2003 ES300 (99K miles) has a "Check Engiine" light came on about a month ago after driving 4 hours straight with 90-100 miles/h.
I reset it by disconnecting battery for 20 seconds.

It was fine for a month. After another long distance trip, "check engine" light came on again.
I took it to the dealer and have them scan the error code.

P0441 - Evaporative Emission Control Purge flow
P0442 - Leak Detected (Small Leak)
P0446 - Vent Control Malfunction

Dealer suggested to replace:
1. Gas tank cap ($35)
2. Whole Canister Assembly ($260)
3. Purge Solenoid Valve (Valve, Vacuum) ($50)

These are parts only price, labor will be another $250.
Dealer reset it again, so "Check Engine" light is off now.

I am planning to replace the gas cap by myself right away.
Any suggestions, ideas, or your experience would be appreciated.
Thank you, fellow CL member...

 

By all means, change the gas cap, also check all the vapor hoses. closely inspect the hoses for splits, cracks.

 

I just got a P0446 on my GS400. Is there anything special about the Lexus Gas cap? Or would any gas cap from the auto parts store work?

 

I would stick with OEM gas caps. Aftermarket ones never seem to seal properly...

 

I have the same codes on my 2000 ES. From extensive research, if all three of these codes pop up, the charcoal canister is the most likely culprit. I highly doubt you should have to pay someone to change it, it's only about a thirty minute job. GL!

 

yeah, make sure you give them your vin so that you can get the correct charcoal canister, it is very easy, and should already include a vsv. i ended up having to do that and the vsv was non returnable.
goodluck
Charley

 

OK. progress report.
I ordered and replace gas tank cap with new one.
Reset the error code by disconnecting battery. Engine error light came back on again about driven half tank of gas.

Next, I will try to change charcol (filter only) canister. fuel filter after that.
Can someone point out where it is on 2003 ES300? I am assuming that it is in engine room somewhere and changing is like (replacing engine air filter).

 

hey there, usually this sign ends up being a vsv switch. i have a brand new one as long as you confirm the pn. i ended up needing the whole canister, but if you read around, most have bad vsv switches. so now im stuck with this new switch.lmk
Charley