Rx300 lexus , getting check engine light and vsc indicators on. autozone ran codes po441,po442,po446,po420.all are evap emissions sys except po420- catalyst sys. efficiency below threshold (bank 1).

Usually means there is a hard fault code in memory.
Go to your local Auto Zone and have the codes pulled and give them to me.

Master Tech Lee Auto Repair Help US

PO420- Catalyst System Efficiency Below Threshold (Bank 1) More than likely a plugged converter or exhaust.Remove the upstream O2 (it'll set a code and be real loud) and then take it for a spin and see if power is restored.
vacuum switching valve may fix the PO441 code. Replacing the charcoal canister could be another thing also. Then your PO446 is EVAP emission control system incorrect purge flow. which could a gas cap, could be a fuel pump seal or pressure sensor, filler neck.

You have codes for a failed exhaust converter,PO420,
EVAP System problem PO440,Incorrect Purge Flow PO441,
Evap Vent Control issues,PO446

Your car is all messed up

That should have been all checked, BEFORE you spent time
in line for inspection

If all the codes are for real & not a false report

You will need new spark plugs,ignition & fuel checked,
new exhaust converters,new evap purge valve,new evap
vent solenoid & possibly vacuum leaks resolved

You either bought someones neglected vehicle or never
do a thing but drive it

May be easier to get a different vehicle,your repair bill
will start at $1,000 & go up, from not being proactive & taking
care of what is required in owning any vehicle (lack of knowledge)

You will need the oxygen sensors also & no, they won't fix the
amount, of what appears to be several failed items, all at one time

So much for Toyota being better than other vehicles

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f80380329#hd1-1-28 Here is what is listed for problems,couldn't find codePO446,click on link to view.

okay po442 isevap leak check gas cap amd right front tower in engine check evap line for broken hose,po131 bad o2 sensor top sensor on rear exhaust manifold,po420 is bad catalyic converter but could be o2 sensor.i would replace o2 first reset eng lingt and go from there, hope this helps good luck.

VSC means Vehicle Stability Control.

It comes on when the sensor send a signal that the vehicle is not stable on the ground.....check the wheel balancing and alignment and the air pressure of your tires too.

Good luck.

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p0446 is an evap code for incorrect purge flow, check the rear vacume switching valve. its above the rear sub frame

P0420 is catalyst system efficiency below threshold (bank 1)

P0440 is evaporative emission control system malfunction

P0441 is evaporative emission control system incorrect purge flow

if the air filter was recently inspected or changed, look for the vacuum hose to be disconnected from the valve located on the air filter cover. another source may be the gas cap either loose or with the tether strap caught under it preventing a proper seal

P0442--Evap Emission Sys. leak detected small leak
P0455--Evap Emission sys. leak detected gross leak
P0456--Evap Emission Sys. leak detected very small leak