1999 Lexus Es300 146K Vsc And Vsc Off Check Engine P0446

[umoms]

I have a 1999 Lexus ES300 with 146k miles and just the other day the VSC and VSC off lights lit up while I was driving...Then a few miles later the Check Engine Light came on. I scanned the codes and got P0446. My mechanic said it will be the Vacuum Switching Valve on the Canister part number 2586062010 but he says its a 2.8hour job. I read elsewhere it should only take 20minutes.... Can someone clarify? Does the car need to be lifted to do this? Also is this the right diagnosis and will this clear the VSC and VSC off lights coming on as well? Becuase when I cleared the check engine code those lights went off as well.

[BoaR]

you happen to be in luck. i was strip searching my evap schematics the other weekend trying to weed out a gas gremlin.

the p0446 code is a vent control malfunction. and refers to code p0441 as a solution. the 441 code is an incorrect purge flow.

the list of "culprits" is as follows:

open/short in vsv circuit for evap, vsv for evap, open/short in vapor pressure sensor circuit, vapor sensor sensor malfunction, open/short in vsv circuit for vapor pressure sensor, malfunction in vsv for vapor pressure circuit, vaccume hose blocked/damaged/disconnected, charcoal canister malfunction.

since it gave you a vent error (446) then the mechanic is prob right in assuming that its the vac valve malfunctioning.

unfortunatly, you are very unlucky because of the year of the car. only the V6 97+98 years were ultra easy access to the stupid evap system. it was placed just under the master brake cylinder once you pop the hood. on these models. ide go with your guess of about 20-25min to get at it, remove/replace etc..

every other year, 4cyl or v6 models had the friggin thing burried behind your gas tank. making it beyond fckin annoying from the looks of it to remove/repair. the canister and half it's guts that attach to it are there also.

you might luck out as there are multiple "valves" dotted in both areas (canister and engine regardless of year) and your busted vac valve might be luckily the engine bay one. it is located under the engine "shield" protector i guess you could call it. undo the 2 hex bolts holding the cover on. and look underneath. should see a round light purple thing with 3 small hoses going into it. thats the front VCV valve. to the left slightly should be a rectangular T shaped tetris piece assembly. thats the VSV for the evap system.

basically its that if you are super lucky. one of those valves jammed or is blocked. if not. behind the gas tank bud... not sure what to tell you.... it's gonna be a painfull thing to get at the canister and the rest of the valves. and i wouldnt be doing it from under a jackstand either... gonna prob need a lift.

and when you clear the codes yes everything should wipe for those. they will come back very soon tho, hehe so dont get your hopes up.

good luck seriously. im fighting with my evap right now too for a stupid gas gremlin prob... and it ain't easy. sigh.

[yeskay]

there is a diy on this installation. check/search the forum.

[Paso Hondo]

there is a diy on this installation. check/search the forum.

Is this an engine performance problem or just something that would cause a fail on a smog check? I have a '99 with the same error. Don't have time to fix it right now.

[Mike B.]

This will not effect engine performance at all. It will not effect reliability at all. The only reason the VSC light is on is the ECM is so crude it cannot distinguish between codes that are pertinent to the vsc system so it shuts it down any time there is an engine code. You could theoretically drive the car forever with that code and never have a seconds issue. It will, unfortunately, stop the car from passing a smog check.