On-Vehicle Inspection

WARNING: This page is about a different car, the 2007 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT AIR-FUEL RATIO COMPENSATION SYSTEM

Measure the voltage between the terminals of the ECM connectors.

Standard

AIR-FUEL RATIO COMPENSATION SYSTEM

Tester Connection	Condition	Specified Condition
A21 (A1A+) -A28 (E2)	Ignition switch ON	3.3 V
A31 (A1A-) -A28 (E2)	Ignition switch ON	2.9 V

NOTE: Connect test leads from the back side of the connector. The connectors should not be disconnected from the ECM.

HINT:

Voltage between the terminals of the ECM is kept constant regardless of the voltage of the A/F sensor.

Fig 1: Identifying Air-Fuel Ratio Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / A/FS B1 S1 and O2S B1 S2.
Warm up the A/F sensor with the engine speed at 2,500 rpm for approximately 2 minutes.

Fig 2: Connecting Intelligent Tester To DLC3
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Keep the engine speed at 2,500 rpm and confirm that the display, when A/FS B1 S1 is selected, is as shown in Fig 3.
HINT:
- The illustration may slightly differ from the display on the intelligent tester.
- Only the intelligent tester displays the waveform of the A/F sensor.
Confirm that the display, when O2S B1 S2 is selected, changes between 0 V and 1 V with the engine speed at 2,500 rpm.

Fig 3: Engine Speed Control Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: The voltage output oscillates more than 8 times in 10 seconds.
CAUTION:
- Perform the check immediately after warming up the engine.
- If the voltage variation could not be verified, warm up the heated oxygen sensor again. If it could not be verified even after warming up the sensor again, check the DTC No. (see DTC CHECK / CLEAR ).

INSPECT FUEL CUT OFF RPM
1. Increase the engine speed to at least 3,500 rpm.
2. Use a sound scope to check for injector operating sounds.
3. Check that injector operating sounds stop momentarily and then resume when the accelerator pedal is released.
  Fuel cut off rpm: 2,500 rpm
  
  Fuel return rpm: 1,200 rpm
VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS
1. Check the appearance.
  1. Check if the indicated portions of the engine assembly are cracked, leaking or damaged.
    HINT:
    
    Disconnection of the engine oil level gauge, oil filler cap, PCV hose, etc. may cause the engine to run improperly. Disconnection, slack or cracks in the air induction system parts between the throttle body and cylinder head will allow air suction and cause the engine to run improperly.
    
    If necessary, repair the engine assembly.
Fig 4: Inspecting Hoses, Connections And Gaskets
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT FUEL CUTOFF VALVE AND FILL CHECK
1. Remove the fuel tank (see REMOVAL ).
2. Connect the pressure gauge to the vent hose port.
3. Install the fuel tank with the vent hose disconnected.
4. Fill the fuel tank with fuel.
5. Apply pressure of 4 kPa (41 gf/cm² , 0.58 psi) to the vent port of the fuel tank.
  HINT:
  
  It is necessary to check the amount of fuel in the fuel tank.
  
  Fig 5: Connecting Pressure Gauge To Vent Hose Port
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Remove the fuel tank cap, and check that the pressure drops.
  If the pressure does not drop, replace the fuel tank assembly.
7. Reconnect the vent line hose to the fuel tank.
  
  Fig 6: Identifying Fuel Tank Cap
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
CHECK AIR INLET LINE
1. Disconnect the air inlet line hose from the charcoal canister.
2. Check that air can flow freely into the air inlet line. If air cannot flow freely into the air inlet line, repair or replace it.
3. Reconnect the air inlet line hose to the charcoal canister.
  
  Fig 7: Identifying Air Inlet Line
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT LEAK DETECTION PUMP (Pressure Sensor)

Measure the power source voltage of the ECM connectors.

Standard

POWER SOURCE VOLTAGE OF ECM CONNECTORS

Tester Connection	Condition	Specified Condition
A18 (VC) - A28 (E2)	Ignition switch ON	4.5 to 5.5 V

If the voltage is not as specified, check the ECM, leak detection pump and wire harness.

Measure the power output of the ECM connectors.

Remove the fuel tank cap.

POWER OUTPUT OF ECM CONNECTORS

Tester Connection	Condition	Specified Condition
D31 (PPMP) - A28 (E2)	Ignition switch ON	1.425 to 4.150 V

If the voltage is not as specified, check the ECM, leak detection pump and wire harness.

Install the fuel tank cap.

Fig 8: Leak Detection Pump Output Voltage Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT PRESSURE SENSOR

Check the power source voltage.
1. Disconnect the pressure sensor connector.
2. Turn the ignition switch to ON.
3. Using a voltmeter, measure the voltage between terminals VC and E2.
  Voltage: 4.5 to 5.5 V
  
  Fig 9: Measuring Voltage Between Terminals VC & E2
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the supply power.

Using SST (turbocharger pressure gauge), apply air to the turbo pressure sensor at the pressures shown in PRESSURE REFERENCE TABLE .
SST 09992-00242

Connect a voltmeter to terminals PIM and E2 of the ECM and measure the output voltage under ambient atmospheric pressure.

Fig 10: Connecting Voltmeter To Terminals PIM & E2 Of ECM

Voltage Increase

PRESSURE REFERENCE TABLE

Applied Pressure [kPa (kgf/cm² , psi)]	Voltage Increase [V]
19.6 (0.20, 2.84)	0.1 to 0.4
39.2 (0.40, 5.69)	0.4 to 0.7
58.8 (0.60, 8.53)	0.7 to 1.0
78.5 (0.80, 11.4)	1.0 to 1.3
98.0 (1.00, 14.2)	1.3 to 1.6

INSPECT AIR PUMP ASSEMBLY
1. Check the operation (see INSPECTION ).