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DTC P1486: EVAP Leak Monitor Pinched Hose Found: Testing

NOTE: Replacing PCM will not correct this problem.
  1. Turn ignition on, with engine off. Using scan tool, read DTCs. If DTC SPECIFIC GOOD TRIP counter is displayed and displayed count is "0", go to next step. If DTC SPECIFIC GOOD TRIP counter is not displayed or displayed count is not "0", go to step  9 .
  2. Turn ignition off. Locate EVAP purge solenoid at right rear of engine compartment. See Figure . Inspect vacuum hose between EVAP purge solenoid and throttle body. If vacuum hose is plugged or kinked, repair vacuum hose as necessary. If vacuum hose is okay, go to next step.
    CAUTION: When performing test procedures, keep lighted cigarettes, sparks, flames and other ignition sources away from test area. Pressurizing fuel tank with less than 3 gallons of fuel may result in an explosion caused by ignition of the fumes. Wear safety glasses when performing test procedures.
  3. To test EVAP system properly, fuel tank should have 3-17 gallons of fuel. Miller Evaporative System Testing Kit (6872A) and Fuel Tank Cap Adapter (8382) are used to perform evaporative system pressure test. Perform pressure pump self-test on evaporative system testing kit by using instructions on cover of evaporative system testing kit. Connect scan tool to Data Link Connector (DLC). Using EVAP system testing kit, fuel tank cap adapter and instructions printed on EVAP system testing kit cover, perform EVAP system pressure pump self-test. Start engine. Using scan tool, go to LEAK DETECTION PUMP TEST and instructions on scan tool. Remove fuel tank cap and install fuel tank cap adapter to fuel tank. Install fuel tank cap to fuel tank cap adapter. Connect hose from evaporative system testing kit to fuel tank cap adapter. Connect EVAP system testing kit positive lead to positive battery terminal. Connect EVAP system testing kit negative lead to negative battery terminal. Set EVAP system testing kit PRESSURE/HOLD valve to OPEN. Set VENT valve to CLOSED. Turn pump timer on and monitor gauge on evaporative system testing kit. When gauge reaches 14 in. H2O, disconnect fuel tank-to-EVAP canister vacuum hose (at EVAP canister) while monitoring gauge on evaporative system testing kit. If pressure decreases when vacuum hose was disconnected, go to next step. If pressure does not decrease when vacuum hose was disconnected, go to step  8 .
  4. Reconnect vacuum hose to EVAP canister. With engine still running and pump timer turned on, allow evaporative system testing kit to obtain 14 in. H2O. Ensure PRESSURE/HOLD valve on evaporative system testing kit is in OPEN position and VENT valve is in CLOSED position. When gauge reaches 14 in. H2O, disconnect EVAP canister-to-EVAP purge solenoid vacuum hose (at EVAP purge solenoid) while monitoring gauge on evaporative system testing kit. If pressure decreases when vacuum hose was disconnected, go to next step. If pressure does not decrease when vacuum hose was disconnected, go to step  7 .
  5. Reconnect vacuum hose to EVAP purge solenoid. With engine still running and pump timer turned on, allow evaporative system testing kit to obtain 14 in. H2O. Ensure PRESSURE/HOLD valve on evaporative system testing kit is in OPEN position and VENT valve is in CLOSED position. When gauge reaches 14 in. H2O, disconnect EVAP canister-to-Leak Detection Pump (LDP) vacuum hose (at LDP) while monitoring gauge on evaporative system testing kit. See Figure . If pressure decreases when vacuum hose was disconnected, replace LDP. If pressure does not decrease when vacuum hose was disconnected, go to next step.
  6. Inspect vacuum hose between EVAP canister and LDP. If vacuum hose is okay and is not restricted, replace EVAP canister. If vacuum hose is defective or restricted, replace pressure hose.
  7. Reconnect vacuum hose to EVAP purge solenoid. With engine still running and pump timer turned on, allow evaporative system testing kit to obtain 14 in. H2O. Ensure PRESSURE/HOLD valve on evaporative system testing kit is in OPEN position and VENT valve is in CLOSED position. Disconnect EVAP purge solenoid-to-EVAP canister vacuum hose (at EVAP canister) while monitoring gauge on evaporative system testing kit. See Figure . If pressure does not decrease when vacuum hose was disconnected from EVAP canister, replace EVAP canister. If pressure decreases when vacuum hose was disconnected from EVAP canister, repair restricted vacuum hose between EVAP canister and EVAP purge solenoid.
  8. Disconnect EVAP purge hose at fuel tank rollover valve while monitoring gauge on evaporative system testing kit. Fuel tank rollover valve is located on top of fuel tank. If pressure decreases when purge hose was disconnected from fuel tank rollover valve, replace hose between fuel tank rollover valve and EVAP canister. If pressure does not decrease when purge hose was disconnected from fuel tank rollover valve, repair obstruction between fuel tank rollover valve and evaporative system testing kit.
  9. At this time, conditions for EVAP leak monitor pinched hose found does not exist or is an intermittent problem. Using scan tool, read FREEZE FRAME data while attempting to duplicate the condition that caused DTC to be set. If DTC P1486: EVAP LEAK MONITOR PINCHED HOSE FOUND now exists, go to step  2 . If DTC P1486: EVAP LEAK MONITOR PINCHED HOSE FOUND does not exist, no problem is indicated at this time. Test is complete.
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