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

Testing & Diagnostics 10 illustrations ~3398 words

EXHAUST GAS RECIRCULATION (EGR) SYSTEM TEST

Note. EGR systems contain different components depending on application. see scheme 93- see scheme 97. When testing EGR system and components, use proper illustration to determine component location.

Note. When performing EGR system test, it may be necessary to monitor engine RPM by using scan tool. Scan tool may be connected to data link connector No. 3 for monitoring engine RPM. see scheme 66- see scheme 72.

Scheme 97

Scheme 97: Camry, Camry Solara, Celica & RAV4
Scheme 97: Camry, Camry Solara, Celica & RAV4
  1. Remove cap and filter from top of EGR vacuum modulator. Ensure filter is clean and in good condition. Clean filter with compressed air (if necessary).
  2. Reinstall filter and cap. Using 3-way connector, install vacuum gauge in vacuum hose on top of EGR valve. This is vacuum hose that goes from top of EGR valve to EGR Vacuum Switching Valve (VSV). Start engine. Ensure engine idles smoothly to ensure proper seating of EGR valve.
  3. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 on data link connector No. 1. see scheme 75- see scheme 78. See «DATA LINK CONNECTOR NO. 1 LOCATIONS»(ref-91238-S08487172112001030600000) table. DATA LINK CONNECTOR NO. 1 LOCATIONS Application Location Camry & Camry Solara Passenger's Side Of Engine Compartment, Near Strut Tower Celica Driver's Side Rear Corner Of Engine Compartment, Near Brake Booster RAV4 On Timing Belt End Of Engine, Above Generator
  4. To test operation of EGR VSV with engine cold, ensure engine coolant temperature is less than 131°F (55°C). Increase and maintain engine speed at 2500 RPM. Ensure no vacuum reading is obtained on vacuum gauge with engine speed at 2500 RPM.
  5. To test operation of EGR VSV with engine warm, operate engine until engine coolant temperature is greater than 140°F (60°C). Operate engine at 2500 RPM again. Ensure a low vacuum reading is obtained on vacuum gauge with engine speed at 2500 RPM.
  6. Disconnect vacuum hose from port "R" on EGR vacuum modulator. (Scheme 97) Using additional hose, connect port "R" on EGR vacuum modulator directly to intake manifold. Operate engine at 2500 RPM again. High vacuum reading should be obtained at 2500 RPM. Engine should misfire due to large amounts of exhaust gas being injected into intake manifold.
  7. Shut engine off. Remove vacuum hose, vacuum gauge and reconnect original vacuum hoses. Remove jumper wire from data link connector No. 1.
  8. To test EGR valve operation, remove and plug vacuum hose located on top of EGR valve. Start engine. Using vacuum pump, apply vacuum directly to EGR valve with engine idling. Engine should run rough or stall if EGR valve is operating properly. If EGR system does not operate as described, each individual component should be tested. Shut engine off.

Fuel EVAP System Test (Camry, Camry Solara, Celica & Corolla)

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

Scheme 98

Scheme 98: Fuel EVAP System Test (Camry, Camry Solara, Celica & Corolla)
Scheme 98: Fuel EVAP System Test (Camry, Camry Solara, Celica & Corolla)

Scheme 99

Scheme 99
Scheme 99

Scheme 100

Scheme 100
Scheme 100

Scheme 101

Scheme 101
Scheme 101

Scheme 102

Scheme 102
Scheme 102
  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 93- 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 66- see scheme 69. 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. See «EVAP VSV LOCATION»(ref-91238-S15273349432001030600000) table. see scheme 93- 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. EVAP VSV LOCATION Application Location Camry & Camry Solara On Bracket Near Air Filter Housing & Driver's Side Strut Tower, & Contains Black 2-Pin Electrical Connector With Violet/White & Black/Yellow Wires Celica On Bracket Near Air Filter Housing & Driver's Side Strut Tower, & Contains Black 2-Pin Electrical Connector With Light Green/Black & Black/Red Wires Corolla On Bracket At Rear Of Air Filter Housing & Contains Black 2-Pin Electrical Connector With Blue/Black & Black Wires
  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-91238-S23642624712001030600000).
  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 98)and (Scheme 99). Charcoal canister is located near fuel tank. see scheme 93- 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-91238-S23642624712001030600000).
  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 98)and (Scheme 99). 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 98)and (Scheme 99).
  14. Apply.58 psi (.040 kg/cm 2 ) air pressure to purge line hose fitting on charcoal canister. Perform STEP 3. (Scheme 98)and (Scheme 99). 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 93- see scheme 95.
  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 98)and (Scheme 99). 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. On Camry, Camry Solara and Corolla, 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 100)
  19. On all models, 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 101)and (Scheme 102). Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding purge port closed. (Scheme 101)and (Scheme 102). 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 101)and (Scheme 102). Ensure no air flows from air inlet port.
  22. Using vacuum pump, apply 1.01 in. Hg of vacuum to purge port. (Scheme 101)and (Scheme 102). 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 101)and (Scheme 102). 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-91238-S23642624712001030600000), «VAPOR PRESSURE SENSOR»(ref-91238-S04078598322001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91238-S24452519192001030600000).

Fuel EVAP System Test (RAV4)

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

Scheme 103

Scheme 103: Fuel EVAP System Test (RAV4)
Scheme 103: Fuel EVAP System Test (RAV4)

Scheme 104

Scheme 104
Scheme 104
  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 purge vacuum hose for EVAP system. 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 70 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 bracket near rear of air filter housing and contains Black 2-pin electrical connector with Black/Red and Pink wires. 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-91238-S23642624712001030600000).
  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 103) Charcoal canister is located in the 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-91238-S23642624712001030600000).
  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. Disconnect necessary electrical connectors and components for removal of charcoal canister. 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 104) Check for clogged filter and/or stuck check valve and diaphragm by applying.26 psi (.018 kg/cm 2 ) air pressure to port "A" while holding port "B" closed. (Scheme 104) 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 104) 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. (Scheme 104)
  15. While holding port "C" closed, use vacuum pump to apply.36 in. Hg of vacuum to port "A". Ensure air flows into "B". (Scheme 104) 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-91238-S23642624712001030600000), «VAPOR PRESSURE SENSOR»(ref-91238-S04078598322001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91238-S24452519192001030600000).

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 105

Scheme 105: Fuel EVAP System Test (Tacoma & 4Runner)
Scheme 105: Fuel EVAP System Test (Tacoma & 4Runner)

Scheme 106

Scheme 106
Scheme 106
  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 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 71and 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. See «EVAP VSV LOCATION»(ref-91238-S26382413242001030600000) table. 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. EVAP VSV LOCATION Application Location Tacoma Bolted To End Of Charcoal Canister & Contains Black 2-Pin Electrical Connector With White/Red & White/Green Wires 4Runner Bolted To End Of Charcoal Canister & Contains Black 2-Pin Electrical Connector With White/Blue & Black/White Wires
  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-91238-S23642624712001030600000).
  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 canister canister. (Scheme 105) Charcoal canister is located in the 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-91238-S23642624712001030600000).
  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. Disconnect necessary electrical connectors and components for removal of charcoal canister. 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 plugs on ports "A" and "B" on charcoal canister. (Scheme 106) Check for clogged filter and/or stuck check valve and diaphragm by applying.21 psi (.015 kg/cm 2 ) air pressure to port "D" while holding port "C" closed. (Scheme 106) 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. (Scheme 106) 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 with port "C" is opened. 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-91238-S23642624712001030600000), «VAPOR PRESSURE SENSOR»(ref-91238-S04078598322001030600000) and «VAPOR PRESSURE SENSOR VACUUM SWITCHING VALVE»(ref-91238-S24452519192001030600000).

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