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1997 Buick LeSabre Question: Check Engine Light

 

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LYNNFARRELL, Agawam, MA, October 20, 2010, 18:35
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I have a fuel evap code 0442 what is this? I was told purge solenoid? Help...

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  • Answer #1

    October 20, 2010, 19:28
     Master

    OBD II Code P0442 means Evaporative System Malfunction, Small Leak.
    A very good source of information about it is found at this article in the RepairPal Encyclopedia here; http://repairpal.com/OBD-II-Code-P0442

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  • Answer #2

    October 20, 2010, 19:59
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     Enthusiast

    This is an emissions problem and better left for the pro's to diagnose rather than just changing parts and hoping for the best... Diagnostic test requires advanced scan tools and an EVAP smoke tester...
    ________________________________________________________________

    Vehicle Application: 1997 Buick Lesabre Custom 3.8L

    Customer Concern: Trouble code P0442.

    Tests/Procedures:
    1. Before starting, verify the customer did not leave the gas cap loose at any time. Also check to see if there is any rust or debris on the filler neck where the gas cap seals against.

    2. Using a scanner, verify the fuel tank pressure sensor voltage reads about 1.5 volts with the gas cap loose. The voltage should be stable.

    3. Check all Evaporative Emission Control System (EVAP) lines, seals and components for leaks.

    4. Verify the purge solenoid allows vacuum to pass through when energized by a scanner. It should seal shut when de-energized.

    5. Install a long hose on the vent solenoid. While commanding the vent solenoid on with a scanner, place the hose to your mouth and suck against the solenoid. The solenoid should be sealed shut when energized by the scanner.

    6. Do this procedure with the vent solenoid several times. Vent solenoids often leak on an intermittent basis.

    Potential Causes:
    Leaking Evaporative Hose
    Loose Gas Cap
    Purge Control Valve
    Defective Vent Control Solenoid

    Tech Tips: Note: The purge solenoid is a normally closed solenoid. The vent solenoid is a normally open solenoid.

    Diagnostic Codes: P0442

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