Question Answered: I have a 1996 toyota avalon,6cyl it has a code p0446
September 14, 2011, 06:55 PM
Customer Concern: The check engine light is on with trouble code P0446.
Tests/Procedures: 1. Verify that the 3-way Vacuum Switching Valve (VSV) on the canister operates correctly. When the VSV is not grounded, the Fuel Tank Pressure (FTP) sensor should be connected to the canister side of the system only. When the VSV is grounded, the FTP sensor should monitor only the fuel tank.
2. Monitor the FTP sensor and unplug the 3-way VSV. Draw vacuum into the canister and verify that it will hold vacuum and the pressure sensor voltage will decrease.
3. Test and verify that the Purge Solenoid and wire harness are all OK. The Purge solenoid should apply vacuum to the charcoal canister when grounded. Also, verify that the hose from the purge solenoid to the charcoal canister does not leak.
Potential Causes: Charcoal Canister
Tech Tips: It is common for the 3-way VSV to stick or not operate correctly or for the charcoal canister to be faulty. The charcoal canister has many check valves and springs built inside, so always replace the canister and 3-way VSV as an assembly so the code does not reset.
Diagnostic Codes: P0446
Question Answered: 110K miles on great car. 8/11 air bag light came on. $450.est.to fix.Necessary?
September 14, 2011, 06:37 PM
This is a possibility.
Vehicle Application: 2004 Chrysler PT Cruiser 2.4L, Vin B
Customer Concern: Air bag light is on. "Driver's Pretensioner Circuit Open" fault code is set. If the code is cleared, it comes right back.
Tests/Procedures: 1. Unplug the driver's side pretensioner. Using a suitable jumper wire, short across the two terminals.
2. Re-check fault codes and see if the code "Drivers Side Pretensioner Circuit Short" is now set.
Potential Causes: Seat Belt Pretensioner
Diagnostic Codes: Drivers Pretensioner Circuit Open
Question Answered: No cabin Heat
September 14, 2011, 06:32 PM
Customer Concern: No heat. Checked the heater water valve, found hot on one side and not on the other. Made sure that temperature control was on hot. Checked for vacuum to the water valve, found none. Removed the control panel and did a smoke test, found a yellow vacuum line under cover for dog house, was not connected to anything, the end was a Y connection. Applied vacuum to the Yellow hose and found vacuum at the water valve. According to vacuum diagram the White vacuum line is the water valve feed. But apparently this is incorrect.
Tests/Procedures: 1. Test for stuck water valve.
2. Locate the Orange hose from the temperature control to the recirculation vacuum valve. Connect the water valve Y into the vacuum line.
Potential Causes: Connection — Hose connection.
Tech Tips: Vacuum line is from the recirculation vacuum actuator control hose. The water valve gets vacuum only when maximum A/C is selected.