Engine Controls - System/component Tests: Other Toyota Celica T200

Power & Ground Circuits

For testing of power and ground circuits, see information PIN VOLTAGE CHARTS article. See ECM LOCATION table for identifying ECM mounting locations.

ECM LOCATION

Note. Figs. (Scheme 16) and (Scheme 17) identify ECM terminals on vehicles which are used for performing tests on various components in this article. For ECM terminal identification on remaining models, see PIN VOLTAGE CHARTS article.

Scheme 16

Scheme 17

AIR TEMPERATURE SENSOR

Air temperature sensor may be referred to as intake air temperature sensor. See INTAKE AIR TEMPERATURE SENSOR under ENGINE SENSORS & SWITCHES.

COOLANT TEMPERATURE SENSOR

Coolant temperature sensor may be referred to as engine coolant temperature sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR under ENGINE SENSORS & SWITCHES.

EGR GAS TEMPERATURE SENSOR

Note. The EGR gas temperature sensor may be referred to as EGR function sensor.

1. Remove EGR gas temperature sensor from side of EGR valve. Place threaded end of sensor and thermometer in container of oil.
2. Attach ohmmeter to electrical terminals. Heat oil and note resistance at specified temperature. See «EGR GAS TEMPERATURE SENSOR SPECIFICATIONS»(ref-21343-S35852030422001010300000) table. Replace EGR gas temperature sensor if resistance is not within specification.

EGR GAS TEMPERATURE SENSOR SPECIFICATIONS

ENGINE COOLANT TEMPERATURE (ECT) SENSOR

1. Ensure ignition is off. Disconnect electrical connector from ECT sensor. The ECT sensor is located in engine coolant passage near cylinder head or thermostat housing. To verify wire colors for proper identification, see wiring diagram in «WIRING DIAGRAMS»(ref-21370) article. NOTE: The ECT may be also identified using appropriate illustration in «THEORY/OPERATION»(ref-21369) article.
2. Using ohmmeter, check resistance between ECT sensor electrical terminals. Resistance should be within specification at designated temperature. (Scheme 18) Replace ECT sensor if resistance is not within specification.

Scheme 18

INTAKE AIR TEMPERATURE SENSOR

1. Ensure ignition is off. Disconnect electrical connector from intake air temperature sensor. Intake air temperature sensor is located in air intake, near air filter. NOTE: Intake air temperature sensor may be also identified using appropriate illustration in «THEORY/OPERATION»(ref-21369) article.
2. Remove intake air temperature sensor. Place threaded end of intake air temperature sensor and thermometer in container of water. Attach ohmmeter between intake air temperature sensor electrical terminals.
3. Heat water and note that resistance is within specification in relation to temperature. (Scheme 19) Replace intake air temperature sensor if defective.

Scheme 19

KNOCK SENSOR

1. Knock sensor(s) are located on the cylinder block. (Scheme 20)and (Scheme 21). Remove knock sensor from cylinder block before testing. See «REMOVE/INSTALL/OVERHAUL»(ref-21431) article.
2. Using ohmmeter, check that no continuity exists between electrical terminal of knock sensor and body of knock sensor. Replace knock sensor if continuity exists.

Scheme 20

Scheme 21

MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR

1. Ensure ignition is off. To check MAP sensor supply voltage, disconnect electrical connector from MAP sensor. See «MAP SENSOR LOCATIONS»(ref-21343-S35053274922001010300000) table. NOTE: MAP sensor may also be identified using appropriate illustration in «THEORY/OPERATION»(ref-21369) article. The MAP sensor has a vacuum hose connected to it and may be identified by wire colors. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-21370) article. MAP SENSOR LOCATIONS Application Location Celica Passenger's Side Of Engine Bay, On Firewall, Near Wiper Motor
2. Turn ignition on. Using voltmeter, measure voltage between terminals VC or VCC and E2 of electrical connector on wiring harness. (Scheme 22) The VC or VCC and E2 terminals are the 2 outer terminals on all models. Voltage should be within specification. See «MAP SENSOR SUPPLY VOLTAGE SPECIFICATIONS»(ref-21343-S18085097272001010300000) table. MAP SENSOR SUPPLY VOLTAGE SPECIFICATIONS Application Volts Celica 4.50-5.50
3. If supply voltage is not within specification, check wiring circuit. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-21370) article. If supply voltage is correct, turn ignition off. Reinstall electrical connector on MAP sensor.
4. To check MAP sensor output voltage, turn ignition on. Disconnect MAP sensor vacuum hose from intake manifold. Connect voltmeter to terminals PIM and E2 of Engine Control Module (ECM). (Scheme 23)and (Scheme 24). See «ECM LOCATION»(ref-21343-S32948159572001010300000) table. ECM LOCATION Application Location Celica Below Passenger's Side Of Dash Underneath Carpet
5. Measure and record output voltage under ambient atmospheric pressure. Attach vacuum pump to MAP sensor.
6. Apply vacuum in specified increments and measure MAP sensor output voltage drop at each increment. See «MAP SENSOR OUTPUT VOLTAGE DROP SPECIFICATIONS»(ref-21343-S16511607302001010300000) table. Replace MAP sensor if output voltage drop is not within specification.

MAP SENSOR OUTPUT VOLTAGE DROP SPECIFICATIONS

Scheme 22

Scheme 23

Scheme 24

PARK/NEUTRAL SWITCH CIRCUIT

Note. Park/neutral switch may be referred to as Park/Neutral Position (PNP) switch.

1. Check for diagnostic trouble codes while cranking the engine. See articles listed below for accessing diagnostic trouble codes: «TESTS W/CODES - 1.8L»(ref-21371) «TESTS W/CODES - 2.2L»(ref-21372)
2. With transmission/transaxle in Park, MIL should flash steady indicating normal operation. With transmission/transaxle in Drive, MIL should flash diagnostic trouble Code 51. This indicates park/neutral switch circuit is okay.
3. If diagnostic trouble Code 51 exists with transmission/transaxle in Park and Drive, check wiring harness between park/neutral switch and Engine Control Module (ECM). See «ECM LOCATION»(ref-21343-S32948159572001010300000) table. If wiring harness is okay, substitute ECM with another ECM and recheck operation. ECM LOCATION Model Location Celica Below Passenger's Side Of Dash Underneath The Carpet
4. If normal operation is displayed by MIL with transmission/transaxle in Park and Drive, check park/neutral switch. See «PARK/NEUTRAL SWITCH»(ref-21343-S32328598472001010300000) under ENGINE SENSORS & SWITCHES. If park/neutral switch is okay, substitute ECM with another ECM and recheck operation. See «ECM LOCATION»(ref-21343-S32948159572001010300000) table.

PARK/NEUTRAL SWITCH

Note. Park/neutral switch may be referred to as Park/Neutral Position (PNP) switch.

A/T Models

Disconnect electrical connector from park/neutral switch at transmission or transaxle. Note terminal identification. (Scheme 25) Using ohmmeter, check for continuity at specified terminals with gearshift in proper positions. See PARK/NEUTRAL SWITCH SPECIFICATIONS table. Replace switch if defective.

PARK/NEUTRAL SWITCH SPECIFICATIONS

Scheme 25

SUB-OXYGEN SENSOR

Note. Sub-oxygen sensor may be used only on California applications on some models. See OXYGEN SENSOR APPLICATION table.

For testing of sub-oxygen sensor, see DETECTION DRIVING PATTERN TEST under TROUBLE CODE 27 in TROUBLE CODE CHARTS in appropriate articles listed below

1. «TESTS W/CODES - 1.8L»(ref-21371)
2. «TESTS W/CODES - 2.2L»(ref-21372)

OXYGEN SENSOR HEATER

Note. Oxygen sensor heater may be used only on California applications on some models. See OXYGEN SENSOR APPLICATION table.

PICK-UP COILS

See PICK-UP COIL AIR GAP and PICK-UP COIL RESISTANCE under IGNITION CHECKS in BASIC TESTING article.

THROTTLE POSITION SENSOR

1. Turn ignition off. Disconnect electrical connector from Throttle Position Sensor (TPS) on throttle body. Note terminal identification. (Scheme 26)and (Scheme 27). NOTE: Some models require that vacuum be applied to throttle opener before checking TPS. See «TPS RESISTANCE SPECIFICATIONS»(ref-21343-S21272961862001010300000) table.
2. Insert specified thickness feeler gauge between throttle stop screw and throttle lever and check resistance or continuity. See appropriate «TPS RESISTANCE SPECIFICATIONS»(ref-21343-S21272961862001010300000) table. Replace or adjust TPS if not within specification.

Scheme 26

Scheme 27

TPS RESISTANCE SPECIFICATIONS

VEHICLE SPEED SENSOR

1. Vehicle speed sensor is located on transmission/transaxle and contains a 3-wire connector. Connect voltmeter and battery voltage to vehicle speed sensor terminals. (Scheme 28)
2. While rotating vehicle speed sensor shaft, ensure voltage changes from zero to at least 11 volts. Voltage should change 4 times per revolution of the shaft. Replace vehicle speed sensor if voltage does not change as specified.

Scheme 28

FUEL PUMP ELECTRONIC CONTROL UNIT

See FUEL DELIVERY under FUEL SYSTEM .

CIRCUIT OPENING RELAY

1. Ensure ignition is off. Remove circuit opening relay. See «CIRCUIT OPENING RELAY LOCATION»(ref-21343-S31034110292001010300000) table. Using ohmmeter, check continuity between specified terminals. (Scheme 29)and (Scheme 30).
2. Check circuit opening relay operation by applying battery voltage and ground and checking continuity between specified terminals. (Scheme 29)and (Scheme 30). Replace circuit opening relay if defective.

Note. Circuit opening relay may also be identified using appropriate illustration in THEORY/OPERATION article or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article.

CIRCUIT OPENING RELAY LOCATION

Scheme 29

Scheme 30

EFI MAIN RELAY

1. Ensure ignition is off. Remove EFI main relay. See «EFI MAIN RELAY LOCATION»(ref-21343-S07558406622001010300000) table. Using ohmmeter, check continuity between specified terminals. (Scheme 31)and (Scheme 32).
2. Check EFI main relay operation by applying battery voltage and ground and checking continuity between specified terminals. (Scheme 31)and (Scheme 32). Replace EFI main relay if defective.

Note. The EFI main relay may also be identified using appropriate illustration in THEORY/OPERATION article or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article.

EFI MAIN RELAY LOCATION

Scheme 31

Scheme 32

IGNITION MAIN RELAY

See IGNITION MAIN RELAY under IGNITION SYSTEM .

FUEL DELIVERY

Note. For fuel system pressure testing, see BASIC TESTING article.

See CIRCUIT OPENING RELAY under RELAYS .

See EFI MAIN RELAY under RELAYS .

Fuel Pump Relay

See FUEL PUMP RELAY under RELAYS .

FUEL CONTROL

Note. Fuel injector solenoid resistor may also be referred to as MFI resistor, SFI resistor or solenoid resistor.

Fuel Injectors

1. Ensure ignition is off. Disconnect electrical connector at fuel injector. Using ohmmeter, measure resistance between fuel injector electrical terminals. Replace fuel injector if resistance is not within specification. See «FUEL INJECTOR RESISTANCE SPECIFICATIONS»(ref-21343-S19944244262001010300000) table.
2. To check fuel injector spray pattern and volume, remove fuel injector. See «REMOVE/INSTALL/OVERHAUL»(ref-21431) article. Disconnect fuel hose from fuel filter outlet. Use Delivery Hose (09268-41045) to install fuel injector between fuel filter and fuel pressure regulator. (Scheme 33)and (Scheme 34).
3. Place fuel injector into a clean graduated container. Place vinyl tube on end of fuel injector to prevent fuel spillage. Install Jumper Wire (SST 09843-18020) between +B and FP terminals of data link connector No. 1. Turn ignition on, with engine off to pressurize fuel system. NOTE: For proper location of data link connector No. 1 and terminal identification, see «BASIC TESTING»(ref-21311) article. Jumper wire is installed in data link connector No. 1 when checking fuel pump operation and fuel pressure.
4. Connect fuel injector tester to fuel injector for 15 seconds. Use Fuel Injector Tester (09842-30070).
5. Measure fuel injector volume and check spray pattern. Test each fuel injector 2-3 times. Replace fuel injector if volume is not as specified. See «FUEL INJECTOR VOLUME SPECIFICATIONS»(ref-21343-S07893411142001010300000) table. NOTE: Ensure difference between fuel injector volume on all fuel injectors is within specification. See FUEL INJECTOR VOLUME SPECIFICATIONS table.
6. Disconnect fuel injector tester. Ensure fuel leakage from end of fuel injector is one drop or less in specified time. See «FUEL INJECTOR LEAKAGE SPECIFICATIONS»(ref-21343-S30000027292001010300000) table. Replace fuel injector if leakage exceeds specified amount. Turn ignition off and remove test equipment.

FUEL INJECTOR RESISTANCE SPECIFICATIONS

FUEL INJECTOR VOLUME SPECIFICATIONS

FUEL INJECTOR LEAKAGE SPECIFICATIONS

Scheme 33

Scheme 34

Note. Fuel pressure control system may also be referred to as fuel pressure-up system.

Fuel Pressure Control System (2.2L CA)

1. Fuel pressure control system uses a fuel pressure control Vacuum Switching Valve (VSV). Fuel pressure control VSV is supplied voltage through EFI main relay.
2. Engine Control Module (ECM) will activate VSV by controlling ground circuit for approximately 90 seconds when restarting engine at normal operating temperature. Locate and remove fuel pressure control VSV. See «FUEL PRESSURE CONTROL VSV LOCATION»(ref-21343-S13774010382001010300000) table. NOTE: Fuel pressure control VSV may also be identified using appropriate illustration in «THEORY/OPERATION»(ref-21369) article or wire color. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-21370) article. FUEL PRESSURE CONTROL VSV LOCATION Application Location Celica 2.2L 5S-FE Calif. Below Intake Manifold
3. Using ohmmeter, check resistance and for continuity between fuel pressure control VSV electrical terminals. Replace fuel pressure control VSV if no continuity exists or resistance is not within specification. See «FUEL PRESSURE CONTROL VSV RESISTANCE SPECIFICATIONS»(ref-21343-S10548259972001010300000) table.
4. Ensure no continuity exists between each electrical terminal and fuel pressure control VSV body. Replace fuel pressure control VSV if continuity exists between electrical connector and fuel pressure control VSV body.
5. Check fuel pressure control VSV operation by applying air pressure to designated area and checking air passage, and then applying battery voltage and ground and retesting. (Scheme 35) Replace fuel pressure control VSV if defective.

FUEL PRESSURE CONTROL VSV RESISTANCE SPECIFICATIONS

Scheme 35

Fuel Cut System

1. Install tachometer. Tachometer must be connected to proper terminals. See IDLE SPEED & MIXTURE in «ADJUSTMENTS»(ref-21340) article. CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. To avoid possible damage to ignitor and/or coil, DO NOT allow tachometer terminal to become grounded.
2. Start engine and warm to normal operating temperature. Ensure all accessories are off. Gradually increase engine RPM to maintain at least specified engine speed. See «FUEL CUT SYSTEM TESTING SPECIFICATION»(ref-21343-S37683701282001010300000) table. FUEL CUT SYSTEM TESTING SPECIFICATION Application Engine RPM 1.8L (7A-FE) 3500 2.2L (5S-FE) 2500
3. Using stethoscope, check for fuel injector operating sound. Ensure when throttle lever is released, fuel injector stops operating momentarily (fuel cut RPM) and then resumes operating (fuel return RPM).
4. Ensure fuel cut RPM (if available) and fuel return RPM are within specification. See «FUEL CUT SYSTEM SPECIFICATIONS»(ref-21343-S24404346312001010300000) table. Shut engine off. Disconnect tachometer.

FUEL CUT SYSTEM SPECIFICATIONS (1)

Cold Start Injector Time Switch

For test procedures, see COLD START INJECTOR TIME SWITCH under ENGINE SENSORS & SWITCHES .

Scheme 36

Scheme 37

A/C IDLE-UP VALVE

1. Remove A/C idle-up valve. See «A/C IDLE-UP VALVE LOCATIONS»(ref-21343-S06031710332001010300000) table. NOTE: The A/C idle-up valve may also be identified using appropriate illustration in «THEORY/OPERATION»(ref-21369) article or wire color. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-21370) article. A/C IDLE-UP VALVE LOCATIONS Application Location 1.8L (7A-FE) Center Of Firewall 2.2L (5S-FE) End Of Intake Manifold On Passenger's Side
2. Using ohmmeter, check resistance between A/C idle-up valve electrical terminals. Replace A/C idle-up valve if resistance is not 30-34 ohms.
3. Ensure no continuity exists between each electrical terminal and body of A/C idle-up valve. To check A/C idle-up valve operation, apply air pressure to designated area and checking air passage, and then applying battery voltage and ground and retesting. (Scheme 38) Replace A/C idle-up valve if defective.

Scheme 38

IDLE AIR CONTROL (IAC) VALVE

1. Warm engine to normal operating temperature. Ensure idle speed is correct. See «ADJUSTMENTS»(ref-21340) article.
2. Apply parking brake and place transmission/transaxle in Neutral. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 of data link connector No. 1. (Scheme 39) Start engine and note engine RPM. NOTE: Data link connector No. 1 is located in engine compartment.
3. Engine RPM should increase to specified engine RPM for 5 seconds, and then return to idle. See «IAC VALVE ENGINE SPEED TESTING SPECIFICATIONS»(ref-21343-S42561835562001010300000) table. IAC VALVE ENGINE SPEED TESTING SPECIFICATIONS Application Engine RPM Celica 900-1300
4. If engine RPM is not as specified, check IAC valve resistance and operation. If engine RPM is within specification, remove jumper wire. Turn ignition off.
5. To check IAC valve resistance, ensure ignition is off. Disconnect electrical connector from IAC valve located on lower area of throttle body. Using ohmmeter, measure resistance between terminal B+ and each remaining terminal. (Scheme 40)and (Scheme 41).
6. Replace IAC valve if resistance is not within specification. See «IAC VALVE RESISTANCE SPECIFICATIONS»(ref-21343-S42318899042001010300000) table.
7. To check IAC valve operation, remove IAC valve from throttle body. Connect battery voltage and ground to proper terminals and ensure valve opens and closes. (Scheme 42)and (Scheme 43). Replace IAC valve if defective.
8. If IAC valve resistance is correct and operates correctly, check wiring circuit between Engine Control Module (ECM) and IAC valve. See «ECM LOCATION»(ref-21343-S32948159572001010300000) table. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-21370) article.

IAC VALVE RESISTANCE SPECIFICATIONS

ECM LOCATION

Scheme 39

Scheme 40

Scheme 41

Scheme 42

Scheme 43

IGNITION SYSTEM

Note. For basic ignition checks, see BASIC TESTING article.

See KNOCK SENSOR under ENGINE SENSORS & SWITCHES .

2.2L

1. Ensure EGR vacuum modulator filter is clean and in good condition. Clean filter with compressed air (if necessary).
2. Using "T" connector, install vacuum gauge in vacuum line to EGR valve. Start engine. Ensure engine runs idles smoothly to ensure proper seating of EGR valve.
3. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 of data link connector No. 1, located in engine compartment. (Scheme 39) NOTE: The EGR system components can be checked with engine coolant temperature less than minimum temperature and engine at specified engine RPM.
4. Operate engine with engine coolant temperature less than minimum temperature and at specified RPM. See «EGR TESTING SPECIFICATIONS»(ref-21343-S01421785022001010300000) table. No vacuum reading should be obtained.
5. Warm engine to normal operating temperature. Operate engine at specified engine RPM again. See «EGR TESTING SPECIFICATIONS»(ref-21343-S01421785022001010300000) table. Ensure a low vacuum reading is now obtained.
6. Disconnect vacuum hose from port "R" of EGR vacuum modulator. (Scheme 44) Using additional hose, connect port "R" of EGR vacuum modulator directly to intake manifold. High vacuum reading should be obtained at specified engine RPM. See «EGR TESTING SPECIFICATIONS»(ref-21343-S01421785022001010300000) table. NOTE: Engine should misfire due to large amounts of exhaust gas being injected into intake manifold.
7. Remove vacuum hose and reconnect original vacuum hose to EGR vacuum modulator. To check EGR valve operation, remove vacuum hose from EGR valve.
8. Using vacuum pump, apply vacuum directly to EGR valve with engine idling. Engine should run rough or stall. If EGR system does not operate as described, each individual component should be tested. Shut engine off. Remove jumper wire from data link connector No. 1.

Scheme 44

1.8L

1. Ensure EGR vacuum modulator filter is clean and in good condition. Clean filter with compressed air (if necessary).
2. Using "T" connector, install vacuum gauge in vacuum line to EGR valve. Start engine. Ensure engine runs idles smoothly to ensure proper seating of EGR valve.
3. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 of data link connector No. 1, located in engine compartment. (Scheme 39) NOTE: The EGR system components can be checked with engine coolant temperature less than minimum temperature and engine at specified engine RPM.
4. Operate engine with engine coolant temperature less than minimum temperature and at specified RPM. See «EGR TESTING SPECIFICATIONS»(ref-21343-S01421785022001010300000) table. No vacuum reading should be obtained.
5. Warm engine to normal operating temperature. Operate engine at specified engine RPM again. See «EGR TESTING SPECIFICATIONS»(ref-21343-S01421785022001010300000) table. Ensure a low vacuum reading is now obtained.
6. To check EGR valve operation, remove vacuum hose from EGR valve. Using vacuum pump, apply vacuum directly to EGR valve with engine idling. Engine should run rough or stall.
7. If EGR system does not operate as described, each individual component should be tested. Shut engine off. Remove jumper wire from data link connector No. 1.

EGR TESTING SPECIFICATIONS

EGR VACUUM MODULATOR

1. Mark locations and disconnect vacuum hoses from EGR vacuum modulator. Block ports "P" and "R" of EGR vacuum modulator. (Scheme 44) NOTE: Ports "P" and "R" are the double ports on side of EGR vacuum modulator. Port "Q" is the single port on side of EGR vacuum modulator.
2. Apply air pressure to port "Q". (Scheme 44) Air should pass freely through air filter side of EGR vacuum modulator.
3. Start and operate engine at specified RPM. See «EGR VACUUM MODULATOR TESTING SPECIFICATIONS»(ref-21343-S16902630452001010300000) table. Repeat test procedures in steps 1) and 2). Strong resistance of airflow should be felt. Replace EGR vacuum modulator if resistance is not felt. Reconnect vacuum hoses to proper locations.

EGR VACUUM MODULATOR TESTING SPECIFICATIONS

EGR VACUUM SWITCHING VALVE (VSV)

Note. When testing EGR VSV, use proper illustration to determine component location. (Scheme 45)-39. The EGR VSV may be referred to as the VSV.

1. Disconnect electrical connector from EGR VSV. Using ohmmeter, check resistance between EGR VSV electrical terminals.
2. Replace EGR VSV if resistance is not within specification. See «EGR VSV RESISTANCE SPECIFICATIONS»(ref-21343-S41760353952001010300000) table. Ensure no continuity exists between each electrical terminal and EGR VSV body. Replace EGR VSV if continuity exists between any electrical terminal and VSV body.
3. Apply air pressure to port "E" (without battery connected). (Scheme 45)and (Scheme 46). Air pressure should flow from port "G". Connect battery voltage and ground to EGR VSV electrical terminals. (Scheme 45)and (Scheme 46). Apply air pressure to port "E". Air pressure should flow through the air filter. Replace EGR VSV if defective.

1. Disconnect electrical connector from EGR VSV. Using ohmmeter, check resistance between EGR VSV electrical terminals.
2. Replace EGR VSV if resistance is not within specification. See «EGR VSV RESISTANCE SPECIFICATIONS»(ref-21343-S41760353952001010300000) table. Ensure no continuity exists between each electrical terminal and EGR VSV body. Replace EGR VSV if continuity exists between any electrical terminal and VSV body.
3. Apply air pressure to port "E" (without battery connected). (Scheme 45)and (Scheme 46). Air pressure should flow through the air filter. Connect battery voltage and ground to EGR VSV electrical terminals. (Scheme 45)and (Scheme 46). Apply air pressure to port "E". Air pressure should not flow through the air filter. Replace EGR VSV if defective.

EGR VSV RESISTANCE SPECIFICATIONS

Scheme 45

Scheme 46

Scheme 47

Scheme 48

Scheme 49

Scheme 50

Scheme 51

Scheme 52

Scheme 53

Scheme 54

Note. The EVAP Thermal Vacuum Valve (TVV) may be referred to as EVAP Thermal Valve (TV).

EVAP Thermal Vacuum Valve

1. Drain cooling system. Remove TVV, located in coolant passage and contains 2 vacuum hoses which go to the charcoal canister and throttle body.
2. Use cool water to cool threaded end of TVV to less than 95°F (35°C). Apply air pressure to top port on TVV. Ensure TVV is closed and no air will pass through lower port.
3. Heat water to greater than 129°F (54°C). Apply air pressure to top port on TVV. Ensure TVV is open and air passes through lower port. Replace TVV if defective. Apply thread sealant to threads of TVV and reinstall. Fill cooling system.

Charcoal Canister

1. Disconnect hoses from charcoal canister. Check for clogged filter and/or stuck check valve by applying low air pressure to port "A". (Scheme 55) Ensure air flows freely from other ports on charcoal canister.
2. Apply low air pressure to port "B". (Scheme 55) Ensure no air flows from any other ports on charcoal canister. Replace charcoal canister if defective.
3. To clean charcoal canister filter, apply 43 psi (3 kg/cm 2 ) air pressure to port "A" while holding port "B" closed. Ensure no activated carbon comes out of charcoal canister. DO NOT attempt to wash out charcoal canister.

Scheme 55

Check Valve

1. Remove check valve from lower hose on charcoal canister. Apply air pressure to Blue or Yellow side of check valve. Air should pass through check valve.
2. Apply air pressure to Black side of check valve. Air should not pass through check valve. Replace check valve if defective.

POSITIVE CRANKCASE VENTILATION (PCV)

1. Remove PCV valve. Attach hose to PCV valve. Blow air from cylinder head side of PCV valve. Ensure air passes easily through PCV valve.
2. Blow air from intake manifold side of PCV valve. Ensure air passes through PCV valve with some restriction. Replace PCV valve if valve does not function as described.

THROTTLE CONTROLS

Note. When testing throttle control systems, tachometer may be required. Ensure tachometer is connected to proper terminals. For tachometer connections, see IDLE SPEED & MIXTURE in ADJUSTMENTS article.

THROTTLE OPENER

1. Warm engine to normal operating temperature. Ensure idle speed is correct. See IDLE SPEED & MIXTURE in «ADJUSTMENTS»(ref-21340) article.
2. Disconnect and plug vacuum hose at throttle opener, located on side of throttle body. Start engine. Maintain engine speed at 2500 RPM. Release throttle and note engine speed. Engine speed should be within specification. See «THROTTLE OPENER SPECIFICATIONS»(ref-21343-S07415705302001010300000) table.
3. If engine speed is not within specification, rotate throttle opener adjusting screw until correct engine speed is obtained. (Scheme 56) Reinstall vacuum hose on throttle opener.

Scheme 56

THROTTLE OPENER SPECIFICATIONS