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Engine Controls - System & Component Testing - V6 & V8: Diagnosis Toyota 4Runner III

Testing & Diagnostics 9 illustrations ~3573 words

EXHAUST GAS RECIRCULATION (EGR) SYSTEM TEST

Note. EGR system is used on Avalon, Camry and Camry Solara models. see scheme 94 When testing EGR system and components, use illustration to determine component location.

Fuel EVAP System Test (Avalon, Camry & Camry Solara)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 231

Scheme 231: Fuel EVAP System Test (Avalon, Camry & Camry Solara)
Scheme 231: Fuel EVAP System Test (Avalon, Camry & Camry Solara)

Scheme 232

Scheme 232
Scheme 232

Scheme 233

Scheme 233
Scheme 233
  1. Inspect all lines and connections for sharp bends or damage. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
  2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP system test kit to EVAP service port. EVAP service port is located in engine compartment, in the purge vacuum hose for EVAP system. see scheme 94
  3. EVAP Vacuum Switching Valve (VSV) must be operated. If scan tool is available, go to next step. If scan tool is not available, go to step 5.
  4. Connect scan tool to data link connector No. 3. see scheme 70- see scheme 72. Start engine. Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate EVAP VSV. Go to step 6.
  5. Disconnect electrical connector at EVAP VSV. EVAP VSV is front VSV on emission control valve set on top of engine, near intake manifold and contains Blue 2-pin electrical connector. see scheme 3and see scheme 94. Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
  6. Check vacuum reading on vacuum gauge with engine idling. Vacuum should be.368-19.713 in Hg. or (5-268 in. H2O) for over 5 seconds. If vacuum is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  7. Shut engine off. If using scan tool to operate EVAP VSV, stop operation of EVAP VSV. Remove scan tool. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
  8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. Perform STEP 1. (Scheme 232) Charcoal canister is located near fuel tank. see scheme 94
  9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying the pressure, the pressure should be 7.7-8.8 in. H2O. If pressure is within specification, remove hose crimper and go to next step. If pressure cannot be maintained, remove hose crimper and check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
  11. To check airtightness of fuel tank and fuel inlet pipe, disconnect EVAP line hose from charcoal canister. Perform STEP 2. (Scheme 232) Apply.58 psi (.040 kg/cm 2 ) air pressure to EVAP line hose so pressure inside the fuel tank is.58 psi (.040 kg/cm 2 ). Check that pressure inside fuel tank holds steady for one minute.
  12. If pressure inside fuel tank holds steady for one minute, reinstall EVAP line hose on charcoal canister. Go to next step. If pressure inside fuel will not hold steady for one minute, check for leaking hoses or pipes at fuel tank and fuel inlet pipe, or for leaks at fuel tank or installed components on fuel tank. If no leaks exist, replace fuel tank and fuel inlet pipe. Reinstall EVAP line hose on charcoal canister. Go to next step.
  13. To check overfill check valve and cut-off valve, disconnect purge line hose and EVAP line hose from charcoal canister, and install cap on air drain hose. Perform STEP 3. (Scheme 232)
  14. Apply.58 psi (.040 kg/cm 2 ) air pressure to purge line hose fitting on charcoal canister. Perform STEP 3. (Scheme 232) Ensure air flows from EVAP line hose when air pressure is applied to purge line hose fitting on charcoal canister. If fuel tank is full of fuel, air may not flow from EVAP line hose, as overfill check valve may be closed. Ensure fuel tank is not full of fuel when checking for airflow at EVAP line hose.
  15. If air flows from EVAP line hose, go to next step. If air does not flow from EVAP line hose, check for restrictions in EVAP line hose and vent line hose. If any hose is restricted, replace hose and recheck operation. If hoses are not restricted, replace overfill check valve and cut-off valve located on top of fuel tank. see scheme 94
  16. Reinstall purge line hose and EVAP line hose on charcoal canister, To check air inlet line, disconnect air inlet line hose from charcoal canister. Perform STEP 4. (Scheme 232) Apply air pressure to air inlet line hose. Air should flow through air inlet line hose. If air flows through air inlet line hose, go to next step. If air does not flow through air inlet line hose, check for restricted air inlet line hose or air inlet line.
  17. Disconnect necessary electrical connectors and components for removal of charcoal canister. Disconnect purge line hose, EVAP line hose and air inlet line hose from charcoal canister.
  18. Push connector on vent line hose toward charcoal canister and pinch both sides of retainer on connector, and then disconnect vent line hose with connector from charcoal canister. (Scheme 233)
  19. Remove charcoal canister and vapor pressure sensor retaining bolts. Remove charcoal canister. Inspect charcoal canister for cracks or damage at all hose fittings. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
  20. To check charcoal canister, install cap on vent port on charcoal canister. (Scheme 234) Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding purge port closed. (Scheme 234) Ensure air flows freely from air drain port.
  21. Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding air drain port and purge port closed. (Scheme 234) Ensure no air flows from air inlet port.
  22. Using vacuum pump, apply 1.01 in. Hg of vacuum to purge port. (Scheme 234) Ensure vacuum does not decrease when air inlet port is closed, and that vacuum decreases when air inlet port is opened.
  23. While holding air inlet port closed, use vacuum pump to apply 1.01 in. Hg of vacuum to EVAP port. (Scheme 234) Ensure air flows into purge port. Remove cap from vent port. Replace charcoal canister if defective.
  24. Reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), vapor pressure sensor and vapor pressure sensor Vacuum Switching Valve (VSV). See «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000), «VAPOR PRESSURE SENSOR»(ref-91239-S20948797662001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91239-S30833741702001030600000).

Fuel EVAP System Test (Land Cruiser)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 234

Scheme 234: Fuel EVAP System Test (Land Cruiser)
Scheme 234: Fuel EVAP System Test (Land Cruiser)

Scheme 235

Scheme 235
Scheme 235
  1. Inspect all lines and connections for sharp bends or damage. Inspect fuel tank for damage, cracks or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
  2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP system test kit to EVAP service port. EVAP service port is located in purge vacuum hose for EVAP system near charcoal canister in engine compartment. see scheme 95
  3. EVAP Vacuum Switching Valve (VSV) must be operated. If scan tool is available, go to next step. If scan tool is not available, go to step 5.
  4. Connect scan tool to data link connector No. 3. see scheme 73 Start engine. Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate EVAP VSV. Go to step 6.
  5. Disconnect electrical connector at EVAP VSV. EVAP VSV is located on driver's side center of intake manifold below intake manifold cover on top of engine and contains Black 2-Pin electrical connector with Blue/Black and Black/Yellow wires. see scheme 95 Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
  6. Check vacuum reading on vacuum gauge with engine idling. Vacuum should be.368-19.713 in Hg. or (5-268 in. H2O) for over 5 seconds. If vacuum is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  7. Shut engine off. If using scan tool to operate EVAP VSV, stop operation of EVAP VSV. Remove scan tool. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
  8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. (Scheme 235) Charcoal canister is located in driver's side of engine compartment. see scheme 95
  9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying the pressure, the pressure should be 7.7-8.8 in. H2O. If pressure is within specification, remove hose crimper and go to next step. If pressure cannot be maintained, remove hose crimper and check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
  11. Remove charcoal canister. Inspect charcoal canister for cracks or damage at all hose fittings. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
  12. Apply.26 psi (.018 kg/cm 2 ) air pressure to port "A" while holding port "B" closed. (Scheme 236) Ensure air flows freely from port "D".
  13. Apply.26 psi (.018 kg/cm 2 ) air pressure to port "A" while holding ports "B" and "D" closed. (Scheme 236) Ensure no air flows from port "C".
  14. Using vacuum pump, apply 1.01 in. Hg of vacuum to port "B". Ensure vacuum does not decrease when port "C" is closed, and that vacuum decreases when port "C" is opened.
  15. While holding port "C" closed, use vacuum pump to apply.39 in. Hg of vacuum to port "A". Ensure air flows into port "B". Replace charcoal canister if defective.
  16. Reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), vapor pressure sensor and vapor pressure sensor Vacuum Switching Valve (VSV). See «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000), «VAPOR PRESSURE SENSOR»(ref-91239-S20948797662001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91239-S30833741702001030600000).

Fuel EVAP System Test (Sienna)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 236

Scheme 236: Fuel EVAP System Test (Sienna)
Scheme 236: Fuel EVAP System Test (Sienna)

Scheme 237

Scheme 237
Scheme 237
  1. Inspect all lines and connections for sharp bends or damage. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
  2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP system test kit to EVAP service port. EVAP service port is located in purge vacuum hose for EVAP system near charcoal canister in engine compartment. see scheme 96
  3. EVAP Vacuum Switching Valve (VSV) must be operated. If scan tool is available, go to next step. If scan tool is not available, go to step 5.
  4. Connect scan tool to data link connector No. 3. see scheme 74 Start engine. Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate EVAP VSV. Go to step 6.
  5. Disconnect electrical connector at EVAP VSV. EVAP VSV is front VSV on emission control valve set on top of engine, near intake manifold and contains Blue 2-pin electrical connector. see scheme 4and see scheme 96. Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
  6. Check vacuum reading on vacuum gauge with engine idling. Vacuum should be.368-19.713 in Hg. or (5-268 in. H2O) for over 5 seconds. If vacuum is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  7. Shut engine off. If using scan tool to operate EVAP VSV, stop operation of EVAP VSV. Remove scan tool. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
  8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. (Scheme 237) Charcoal canister is located in driver's side of engine compartment. see scheme 96
  9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying the pressure, the pressure should be 7.7-8.8 in. H2O. If pressure is within specification, remove hose crimper and go to next step. If pressure cannot be maintained, remove hose crimper and check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
  11. Remove charcoal canister. Inspect charcoal canister for cracks or damage at all hose fittings. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
  12. Install plug on port "E" on charcoal canister. (Scheme 238) Apply.26 psi (.018 kg/cm 2 ) air pressure to port "A" while holding port "B" closed. (Scheme 238) Ensure air flows freely from port "D".
  13. Apply.26 psi (.018 kg/cm 2 ) air pressure to port "A" while holding ports "B" and "D" closed. (Scheme 238) Ensure no air flows from port "C".
  14. Using vacuum pump, apply 1.01 in. Hg of vacuum to port "B". Ensure vacuum does not decrease when port "C" is closed, and that vacuum decreases when port "C" is opened.
  15. While holding port "C" closed, use vacuum pump to apply 1.01 in. Hg of vacuum to port "A". Ensure air flows into port "B". Replace charcoal canister if defective.
  16. Remove plug from port "E" and reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), vapor pressure sensor and vapor pressure sensor Vacuum Switching Valve (VSV). See «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000), «VAPOR PRESSURE SENSOR»(ref-91239-S20948797662001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91239-S30833741702001030600000).

Fuel EVAP System Test (Tacoma & 4Runner)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 238

Scheme 238: Fuel EVAP System Test (Tacoma & 4Runner)
Scheme 238: Fuel EVAP System Test (Tacoma & 4Runner)

Scheme 239

Scheme 239
Scheme 239
  1. Inspect all lines and connections for sharp bends or damage. Inspect fuel tank for damage, cracks or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
  2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP system test kit to EVAP service port. EVAP service port is located in purge vacuum hose for EVAP system near charcoal canister in engine compartment. see scheme 97
  3. EVAP Vacuum Switching Valve (VSV) must be operated. If scan tool is available, go to next step. If scan tool is not available, go to step 5.
  4. Connect scan tool to data link connector No. 3. see scheme 75and see scheme 76. Start engine. Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate EVAP VSV. Go to step 6.
  5. Disconnect electrical connector at EVAP VSV. EVAP VSV is located on end of charcoal canister. see scheme 97 Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
  6. Check vacuum reading on vacuum gauge with engine idling. Vacuum should be.368-19.713 in Hg. or (5-268 in. H2O) for over 5 seconds. If vacuum is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  7. Shut engine off. If using scan tool to operate EVAP VSV, stop operation of EVAP VSV. Remove scan tool. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
  8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. (Scheme 239) Charcoal canister is located in driver's side of engine compartment. see scheme 97
  9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying the pressure, the pressure should be 7.7-8.8 in. H2O. If pressure is within specification, remove hose crimper and go to next step. If pressure cannot be maintained, remove hose crimper and check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000).
  10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
  11. Remove charcoal canister. Remove all vacuum switching valves from charcoal canister. Inspect charcoal canister for cracks or damage at all hose fittings. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
  12. Install plugs on ports "A" and "B". see scheme 111 Apply.21 psi (.015 kg/cm 2 ) air pressure to port "D" while holding port "C" closed. see scheme 111 Ensure air flows freely from port "E".
  13. Apply.21 psi (.015 kg/cm 2 ) air pressure to port "D" while holding ports "C" and "E" closed. see scheme 111 Ensure no air flows from port "F".
  14. Using vacuum pump, apply.87 in. Hg of vacuum to port "C". Ensure vacuum does not decrease when port "F" is closed, and that vacuum decreases when port "F" is opened.
  15. While holding port "F" closed, use vacuum pump to apply.87 in. Hg of vacuum to port "D". Ensure vacuum does not decrease when port "C" is closed, and that vacuum decreases when port "C" is opened. Replace charcoal canister if defective.
  16. Remove plugs and reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), vapor pressure sensor and vapor pressure sensor Vacuum Switching Valve (VSV). See «EVAP VACUUM SWITCHING VALVE»(ref-91239-S01627254152001030600000), «VAPOR PRESSURE SENSOR»(ref-91239-S20948797662001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91239-S30833741702001030600000).

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