Quote:
Originally Posted by TX4Running
Got the CEL, VSC TRAC, and VSC OFF lights. Codes show to be P0440, P0441, and P0446. There's a lot of info about the P0446 out there. I'm looking for solutions ONLY from people who have corrected the problem legally. We have annual inspections that are required so I cannot bypass anything or ignore it.
I know the gas cap thing is not the solution. Is the replacement of the charcoal canister a likely solution?
I read that someone corrected their issue by replacing a filler pipe in bad condition. My filler pipe is in great condition. However, I cannot fill up by just leaving the pump nozzle in my filler pipe. I have to hold it at a specific angle at least 75% of the time. This now is my wife's vehicle and she said she has topped off the fuel tank in the past. Once she realized where I was going with the questioning she said she hadn't done it in at least 6 months. Through powers of factoring for what she says and what she means, she probably topped it off last week. Yet I digress. If topping off was the cause, will time correct the problem assuming no more topping off problems? Any ideas are much appreciated. Thanks.
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Straight from the ol' tech archives. Basically data collected from techs that have seen the same combination of codes, the diagnosis, and the number of times each item was verified as the correct repair.
Pretty telling since you have the exact 3 codes!
Vehicle Application:
1999 4Runner 3.4 2003 Sequoia 4.7
2000 4Runner 3.4 2000 Solara 2.2
2001 4Runner 3.4 2000 Solara 3.0
2002 4Runner 3.4 2002 Tacoma 3.4
2004 4Runner 4.0 2003 Tacoma 3.4
1999 Camry 2.2 2004 Tacoma 3.4
2000 Camry 2.2 2003 Tundra 3.4
2000 Camry 3.0 2004 Tundra 3.4
2002 Sequoia 4.7
Customer Concern:
Engine runs, but the Malfunction Indicator Light (MIL) is on with codes P0440, P0441 and P0446.
Average Reported Mileage:
112049
Tests/Procedures:
1. Verify that the Vacuum Switching Valve (VSV) for the pressure sensor (located on the canister) operates correctly. This is a normally closed (N.C.) valve. When energized, it should open. When de-energized, an internal spring should close the valve.
2. Verify that the canister closed valve (located on the air filter housing) closes and does not stick closed when operated. This is a normally open (N.O.) valve. When it is grounded, it closes, and it should never stick closed.
3. If both solenoids operate correctly and are not sticking, inspect for a restriction in the Evaporative Emission (EVAP) lines that could affect how the canister vents after a leak test is performed.
4. Verify that the fuel cap is a factory part. If the fuel cap leaks or does not hold the correct amount of vacuum when the system checks for a leak, all the codes will set.
Tech Tips:
If possible, use a scan tool to turn these two solenoids on and off. This is a good way to test the operation of the internal drivers of the Engine Control Module (ECM) and the wiring harness. Refer to Toyota TSB #EG005-01 and #EG013-03 for additional information on the EVAP system operation.
Diagnostic Codes
P0440
P0441
P0446
Confirmed Fix
83 - Charcoal Canister
29 - Fuel Filler Cap
18 - Evaporative Emissions (EVAP) Vacuum Switching Valve (VSV)