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Home >> Mercury >> 1997 >> Cougar/XR7 V8-4.6L VIN W >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> HX - Evaporative Emission (EVAP) Monitor and System >> HX51 - HX60

HX51 - HX60




HX51 - Check For Fuel Vapor Leak In The EVAP Canister-CV Solenoid Assembly

NOTE: Remove the EVAP canister-CV solenoid assembly if it is not accessible to perform the following step.

- Plug the canister vent hose assembly or close (tape CV filter shut) the CV solenoid to atmosphere.
- Pressurize the EVAP system to 3.48 kPa (14 in-H 20) at evaporative service port.
- Slowly pass the detector probe around the EVAP canister-CV solenoid assembly.

Is an audible change around the EVAP canister-CV solenoid assembly indicated?

YES TEST the EVAP canister-CV solenoid assembly for leaks. REPLACE damaged component. PERFORM leak test on EVAP canister-CV solenoid assembly prior to installation in vehicle. Then, REPEAT Pinpoint Test Step HX45 to VERIFY fuel vapor leak no longer exists, disregarding the Action To Take direction in that step.

For EVAP system passing leak the test:

PERFORM the Vehicle Preparation for Monitor Repair Verification Drive Cycle and RERUN Evaporative Emission Running Loss Monitor Repair Verification Drive Cycle.

For EVAP system not passing the leak test:

GO to HX52.
NO GO to HX52.

HX52 - Check For EVAP System Leak From EVAP Test Port To EVAP Canister Assembly


- Disconnect the EVAP canister tube (from the fuel tank) at the fuel vapor tee between the EVAP canister purge valve and EVAP canister (or at the F-fitting on the EVAP canister).
- Plug (cap) the fuel vapor tee (or F-fitting on the EVAP canister).
- Close the CV solenoid closed by accessing Output Test Mode on the scan tool.
- Pressurize the EVAP system to 3.48 kPa (14 in-H 20) at the evaporative service port.

NOTE: The Rotunda Engine EAR Amplifier (107-R2100) is an optional tool to be used if noise level hinders the effectiveness of the ultra-sonic detector.

- Access the ultra-sonic detector from the EVAP System Leak Tester kit.
- Slowly pass the detector probe from the EVAP return tube (intake manifold to EVAP canister purge valve) to the EVAP canister assembly.

Is a sudden audible change indicated?

YES REPLACE fuel vapor hoses/tubes or damaged components as necessary. REMOVE plug from the fuel vapor tee or F-fitting. RECONNECT the EVAP canister tube. GO to HX53.
NO GO to HX54.

HX53 - Verification Of Repair Between EVAP Test Port To EVAP Canister Assembly

- Perform the leak test outlined in Pinpoint Test Step HX45, disregarding the Action To Take direction in that step.

Does the pressure on the EVAP system stay above 1.99 kPa (8 in-H 20) and pass the leak test?

YES REMOVE EVAP System Leak Tester equipment from evaporative test port. Make sure fuel filler cap is off before proceeding to next Pinpoint Test Step. GO to HX56.
NO REMOVE EVAP System Leak Tester equipment from evaporative test port. GO to HX54.

HX54 - Check For EVAP System Leak From Fuel Tank To EVAP Canister Tube

NOTE: Remove the fuel vapor vent valve and fuel vapor control valve tube assemblies if they are not accessible to perform the following step.

- Disconnect the EVAP canister tube (from the fuel tank) at the fuel vapor tee between the EVAP canister purge valve and EVAP canister.
- Plug the open end of the EVAP canister tube (or at the F-fitting on the EVAP canister).
- Install the EVAP System Leak Tester at the fuel filler pipe.
- Pressurize the EVAP system from 6.47 to 6.97 kPa (26 to 28 in-H 20).

NOTE: The Rotunda Engine EAR Amplifier (107-R2100) is an optional tool to be used if noise level hinders the effectiveness of the ultra-sonic detector.

- Access the ultra-sonic detector from the EVAP System Leak Tester kit.
- Slowly pass the detector probe over the fuel filler pipe, fuel tank, fuel vapor vent valve assembly, fuel vapor control valve tube assembly, FTP sensor and the EVAP canister tube (fuel vapor tube from fuel vapor control valve to EVAP canister).

Is a sudden audible change indicated?

YES LEAVE EVAP System Leak Tester equipment connected at the fuel filler pipe. REPLACE damaged fuel vapor hoses/tubes. After repair, GO to HX55.
NO REMOVE plug from EVAP canister tube. RECONNECT the EVAP canister tube and fuel filler cap. TRANSFER EVAP System Leak Tester equipment from the fuel filler pipe to the evaporative test port. RERUN the EVAP system leak test outlined in Pinpoint Test Step HX45 to VERIFY a leak no longer exists. GO to HX56.

HX55 - Verification Of Repair Between Fuel Tank And EVAP Canister

- Pressurize the EVAP system to 3.48 kPa (14 in-H 20) and perform leak test.

Does the pressure on the EVAP system stay above 1.99 kPa (8 in-H 20) and pass the leak test?

YES REMOVE plug from EVAP canister tube. RECONNECT the EVAP canister tube and fuel filler cap. TRANSFER EVAP System Leak Tester equipment from the fuel filler pipe to the evaporative test port. RERUN the EVAP system leak test outlined in Pinpoint Test Step HX45 to VERIFY a leak no longer exists. GO to HX56.
NO REPEAT Pinpoint Test Step HX54 to isolate the additional source of the fuel vapor leak.

HX56 - Check For Fuel Tank Pressure Sensor Function With Fuel Filler Cap Removed

- Remove fuel filler cap.
- Connect scan tool.
- Key on, engine off.
- Access the VPWR PID.
- If VPWR PID is not greater than 10.5 volts less, refer to Pinpoint Test Step HX61 to charge the system. Then, return to this pinpoint test step.
- Access the FTP V PID.
- Key off.

Was the FTP V PID voltage between 2.40 to 2.80 volts with the fuel filler cap off?

YES GO to HX57.
NO REPLACE FTP sensor. REPEAT this Pinpoint Test Step to VERIFY the repair. GO to HX57.

HX57 - Fuel Tank Pressure Sensor Functional Check With Pressure Applied To EVAP System

- Install the EVAP System Leak Tester equipment at the fuel filler pipe.
- Plug the canister vent hose assembly or close (tape CV filter shut) the CV solenoid to atmosphere.
- Key on, engine off.
- Access the FTP (FTP V) PID on the scan tool.
- Pressurize the EVAP system to 3.48 kPa (14 in-H 20).
- Key off.

Was the FTP (FTP V) PID reading [3.11 to 3.86 kPa (12.5 to 15.5 in-H 20)] (4.22 to 4.90 volts) with pressure applied to EVAP system?

YES REMOVE the EVAP System Leak Tester equipment from fuel filler pipe. RECONNECT fuel filler cap. REMOVE the plug from the canister vent hose assembly or tape from the CV solenoid. GO to HX58.
NO REPLACE damaged FTP sensor. REPEAT Pinpoint Test Step HX56 and HX57 to VERIFY repair. GO to HX58.

HX58 - Check For EVAP Canister Purge Valve Operation With Engine At Idle

- Remove plug and connect EVAP return tube at the intake manifold vacuum source.
- Key on, engine off.
- Access EVAPPDC PID and FTP V PID on the scan tool.
- Start engine. Observe the EVAPPDC PID and FTP V PID.
- Idle engine until EVAPPDC PID reaches a minimum of 40% duty cycle.

Does the FTP V PID read less than 2.60 volts?

YES PERFORM the Vehicle Preparation for Monitor Repair Verification Drive Cycle and RERUN Evaporative Emission Running Loss Monitor Repair Verification Drive Cycle.
NO GO to HX59.

HX59 - Check For Intake Manifold Vacuum To EVAP Canister Purge Valve

NOTE: At high elevations the intake manifold vacuum source readings at both the input port vacuum hose and EVAP return tube must be at least 33.77 kPa (10 in-Hg).

- Disconnect the input port vacuum hose and EVAP return tube at the EVAP canister purge valve.
- Install a vacuum gauge in kPa (in-Hg) to the open end of the input port vacuum hose and plug the open end of the EVAP return tube.
- Start engine.
- Observe vacuum gauge for manifold vacuum and record reading.
- Key on, engine off.
- Install the vacuum gauge to the EVAP return tube and plug the open end of the input port vacuum hose.
- Again, start engine.
- Again, observe the vacuum gauge for manifold vacuum.

Are both vacuum gauge readings between 47.28 and 67.54 kPa (14 and 20 in-Hg)?

YES REMOVE vacuum gauge. REPLACE EVAP canister purge valve. RECONNECT input port vacuum hose and EVAP return tube to the EVAP canister purge valve. RERUN EVAP System Leak Test at evaporative test port to VERIFY the repair. PERFORM the Vehicle Preparation for Monitor Repair Verification Drive Cycle and RERUN Evaporative Emission Running Loss Monitor Repair Verification Drive Cycle.
NO CHECK for blockage in the input port vacuum hose or EVAP return tube. CHECK intake manifold tree or port for debris or obstructions. REPLACE or REPAIR as necessary. If fuel vapor hoses/tube are replaced, RERUN EVAP System leak test at evaporative test port to VERIFY the repair. REPEAT Pinpoint Test Step HX58 to VERIFY blockage repair.

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