JAB

1999 RX300, 190K; no recent work. Today a code '441' pops up, 'evaporative control flow' or words to that effect. What specifically generates this code? TIA. I have reset it, but would like to know what to look for if it returns.

hypervish

I believe that's for the EVAP Canister. How's your gas cap? Does it make a "swoosh" noise when you open it, like pressure being relieved?

JAB

Gas cap is original. Yes, it makes a 'swoosh' sound as I unscrew it.

JAB

Further research reveals that the code 441 means 'evaporative emission control system incorrect purge flow.' Involves the vacuum switching valve (VSV) and the charcoal cannister. If code returns, remove and replace vacuum hoses between vsv and cannister (if the hose is metal, simply clean it.) If problem persists, replace vsv and cannister with new parts. Anyone experienced this?

hypervish

Has it been overfilled? Do you top off the tank?

JAB

Tank is not presently full; in fact, it is nearing empty. And no, when the gas pump shuts off, I do not 'overfill.'

Lexmex

I get P0446 pending because I run my tank down to almost nothing (not a good idea, but it's a habit I've never lost even after being 3 years away from running 1/4 mile at the track back in Mexico). However, I regularly see it.

osalman

The local shop told me a solenoid valve in the EVAP canister (VRV?) is malfunctioning on my wife's 2000 RX300 with 204K miles on it. Were is the the canister located and is it possible to replace the valve? Today we received a notice that the vehicle is due for a Maryland Emissions Inspection.

defo

iTrader: (6)

I had the same P0441 code....so I changed the gas cap and deleted the code. The light came back on, then I replaced the PCV, deleted the code and it has not come back on. Both items were very inexpensive and eventually fail, so try replacing them first.

JAB

I will replace the PCV and see what happens. If that doesn't cure the problem, I'll take the next step, but dealer parts dept says that on my car there are 2 VRV (each with different p/n); how do I know which one may have gone bad?

osalman

I removed, cleaned, and bench tested the VSV at the canister. It worked flawlessly and didn't seem to be obstructed, so I put it back in service. With the car running it didn't seem to be switching and the tubing to the VSV didn't seem to have a vacuum. Does anyone know how to verify if the canister is functioning using a vacuum gage or how to trouble shoot it?

JAB

Where is the cannister? And, I'm told there are two VSVs. Where are they?

mga555

I've had the 441 code for a couple years and have been able to get it through the NY emissions inspection. The computer doesn't check the evap system if the gas tank is over 7/8 full. Here is what to do. Fill the tank then clear the code. Drive the car for about 30-40 miles and keep the gas tank full. The CEL should stay off. Driving will reset the monitors in the computer except the evap system. In NY for a 1999 car, 2 monitors can be incomplete and still pass. Hope this helps.

defo

iTrader: (6)

Since I replaced the PCV, I have driven about 1400 miles and the CEL has not come back on.

JAB

I replaced the PCV but code returned. Today I removed the cannister-adjacent VSV and a short length of hose that may have rotted; the clamps fell off in my hands they were so rusted. I will try to buy the VSV at the Toyota dealer; anybody got the p/n? Hoping for the best, TIA.