Part 2

2AZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P1603, P1605: Engine Stall History

23. INSPECT FUEL PUMP

(a) Inspect the fuel pump Inspection.

NG -- REPLACE FUEL PUMP Removal

OK -- CHECK FUEL PUMP CONTROL CIRCUIT Fuel Pump Control Circuit

24. CHECK FUEL SYSTEM

(a) Check for foreign matter such as iron particles around the fuel pump (fuel pump, fuel pump filter and inside the fuel tank), and for signs that the fuel pump was stuck.

Result

HINT
If there is foreign matter such as iron particles on the fuel pump, fuel filter or fuel tank, remove the foreign matter.

B -- REPLACE MALFUNCTIONING PARTS

A -- REPAIR OR REPLACE FUEL SYSTEM Components

25. READ FREEZE FRAME DATA

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.

Result

HINT
- Try to operate the vehicle under the conditions recorded in the freeze frame data which were present when the malfunction occurred. Confirm the data at this time and the data when the engine is idling (engine warmed up, no load, and shift lever in D or N) and compare these data with the freeze frame data.
- *1: If the mass air flow meter is malfunctioning and incorrectly measures the intake air volume to be higher than the actual volume of air flowing through the intake manifold, the freeze frame data will show a high engine load value.
- *2: As the air fuel ratio sensor output is low before the sensor warms up, the value at that time cannot be used for diagnosis. If the air fuel ratio sensor is malfunctioning and constantly outputs a value indicating the air-fuel ratio is rich, the actual air-fuel ratio will become lean and the engine may stall.

B -- PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)

C -- READ FREEZE FRAME DATA
A -- Continue to next step.

26. INSPECT MASS AIR FLOW METER

(a) Remove the mass air flow meter.

(b) Check for foreign matter in the air flow passage of the mass air flow meter.

Result

HINT
Even if the results are normal, the mass air flow meter may have been malfunctioning. Continue this inspection procedure until step 34, and if there are no problems with other parts, replace the mass air flow meter (refer to step 57).

B -- READ FREEZE FRAME DATA

A -- REPLACE MASS AIR FLOW METER Removal

27. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)

(a) Connect the Techstream to the DLC3.

(b) Start the engine, turn off all accessory switches and warm up the engine until the engine coolant temperature stabilizes.

(c) Idle the engine.

(d) Using the Techstream, select the [Control the Injection Volume] Active Test.

(e) Read the output voltage from the air fuel ratio sensor when increasing and decreasing the fuel injection volume.

Standard:

Result

HINT
- The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
- Even if the results are normal, the air fuel ratio sensor may have been malfunctioning. Continue this inspection procedure until step 34, and if there are no problems with other parts, replace the air fuel ratio sensor (refer to step 57).

B -- READ FREEZE FRAME DATA
A -- Continue to next step.

28. CHECK HARNESS AND CONNECTOR (A/F SENSOR POWER SOURCE)

(a) Check the harnesses and connectors, referring to DTC P0031 inspection procedure P0031.

HINT
- Jiggle the wire harness and connector to increase the likelihood of detecting malfunctions that do not always occur.
- Make sure there is not an excessive amount of force applied to the wire harness.

NG -- REPAIR POWER SOURCE CIRCUIT P0031
OK -- Continue to next step.

29. CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM)

(a) Check the harnesses and connectors, referring to DTC P2237 inspection procedure P2237.

HINT
- Jiggle the wire harness and connector to increase the likelihood of detecting malfunctions that do not always occur.
- Make sure there is not an excessive amount of force applied to the wire harness.

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE AIR FUEL RATIO SENSOR Removal

30. READ FREEZE FRAME DATA

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.

Result

HINT
- *1: A long time had elapsed after stopping the engine.
- *2: A long time had not elapsed after stopping the engine.

B -- READ FREEZE FRAME DATA
A -- Continue to next step.

31. READ FREEZE FRAME DATA

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, confirm the vehicle conditions present when the DTC was stored which are recorded in the freeze frame data Freeze Frame Data.

Result

HINT
This step is not directly related to engine stall.

B -- INSPECT ENGINE COOLANT TEMPERATURE SENSOR

C -- CLEAR DTC
A -- Continue to next step.

32. INSPECT THERMOSTAT

(a) Inspect the thermostat Testing and Inspection.

Result

HINT
This step is not directly related to engine stall.

B -- INSPECT ENGINE COOLANT TEMPERATURE SENSOR

A -- REPLACE THERMOSTAT Removal

33. READ FREEZE FRAME DATA

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.

Result

HINT
*: Use an actual outside temperature estimated from the Initial Intake Air Temp, Ambient Temp for A/C, and (if possible) the weather when the DTC was detected.

B -- CLEAR DTC
A -- Continue to next step.

34. INSPECT ENGINE COOLANT TEMPERATURE SENSOR

(a) Inspect the engine coolant temperature sensor Testing and Inspection.

Result

HINT
Even if the results are normal, the engine coolant temperature sensor may have been malfunctioning. If there are no problems with other parts, replace the engine coolant temperature sensor (refer to step 57).

B -- REPLACE MALFUNCTIONING PARTS

A -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal

35. READ FREEZE FRAME DATA

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.

Result

HINT
- Try to operate the vehicle under the conditions recorded in the freeze frame data which were present when the malfunction occurred. Confirm the data at this time and the data when the engine is idling (engine warmed up, no load, and shift lever in D or N) and compare these data with the freeze frame data.
- *1: If the throttle body assembly has a temporary problem in which it cannot fully close, the intake air volume and engine speed increase. As a result, the ISC learning amount becomes less than the standard. At this time, if the throttle body assembly returns to normal and fully closes, the intake air volume will be insufficient and the engine may stall.
- *2: If carbon accumulates on the throttle body assembly and the intake air volume decreases, the ISC learning amount is increased to maintain the idling speed. If this situation continues, the ISC learning amount reaches the upper limit, the idling speed cannot be maintained causing idling to become unstable, and the engine may stall.

B -- INSPECT THROTTLE BODY

C -- PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT LINEAR)
A -- Continue to next step.

36. INSPECT THROTTLE BODY

(a) Check for foreign matter and signs that the throttle body assembly was stuck, and also check that the valve and shaft move smoothly during operation.

Result

HINT
Even if the results are normal, the throttle body assembly may have been malfunctioning. Continue this inspection procedure until step 41, and if there are no problems with other parts, replace the throttle body (refer to step 57).

B -- PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT LINEAR)

A -- REPLACE THROTTLE BODY Removal

37. INSPECT THROTTLE BODY

(a) Check if carbon is in the air flow passage of the throttle body.

Result