Toyota Tundra. Manual — part 1248

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Exhaust gas pulsation is detected by the pressure sensor despite the ECM commanding the ASV to close.

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Exhaust gas pulsation is not detected by the pressure sensor despite the ECM commanding the ASV to
open.

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

All:

TYPICAL ENABLING CONDITIONS

Case 1:

Related DTCs

P2440: Air control valve stuck open
P2441: Air control valve stuck closed
P2442: Air control valve stuck open
P2443: Air control valve stuck closed

Required Sensors/Components (Main)

Pressure sensor

Required Sensors/Components (Related)

-

Frequency of Operation

Once per drive cycle

Duration

7 seconds

MIL Operation

1 driving cycles: P2440, P2442
2 driving cycles: P2441, P2443

Sequence of Operation

None

Monitor runs whenever following DTCs not present

P0010 - P0022: VVT system
P0031 - P0052: Front A/F sensor heater
P0102 - P0103: MAF sensor
P0110 - P0113: IAT sensor
P0115 - P0118: ECT sensor
P0120 - P2125: TP sensor
P0125: Closed loop
P0171 - P0175: Fuel trim
P0300 - P0306: Misfire
P0325 - P0333: Knock sensor
P0335: CKP sensor
P0340 - P0346: VVT sensor
P0351 - P0356: Igniter
P0441 - P2420: EVAP system
P0500: VSS
P2195 - P2A03: A/F sensor
P2430 - P2433: AIR pressure sensor

Battery voltage

11 V or more

Atmospheric pressure

45 kPa (337.5 mmHg) or more

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

TYPICAL ENABLING CONDITIONS

Case 2:

TYPICAL ENABLING CONDITIONS

Case 3:

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

Condition 1:

TYPICAL MALFUNCTION THRESHOLDS

Condition 2:

TYPICAL MALFUNCTION THRESHOLDS

Condition 3:

TYPICAL MALFUNCTION THRESHOLDS

Condition 4:

Time after secondary injection operation begins

5 seconds or more

Secondary air injection pump

ON

Secondary air injection switching valve

ON

Engine speed

Less than 3750 RPM

Delay time after engine started

5 seconds or more

Pressure sensor malfunction

Not detected

Secondary air injection pump

OFF

Engine speed

Less than 3750 RPM

Secondary air injection system monitor during secondary air injection ON

Completed

Pressure sensor malfunction

Not detected

Cumulative intake air amount

177 g/sec. or more

AIR pump

OFF

AIR valve

OFF

AIR status

OFF

Pressure sensor malfunction

Not detected

AIR pressure during AIR ON

1 kPa or more and pulse is generated

AIR pressure during AIR ON

Less than 1 kPa and pulse is generated

AIR pressure during AIR ON

1 kPa or more and pulse is not generated

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

TYPICAL MALFUNCTION THRESHOLDS

Condition 5:

TYPICAL MALFUNCTION THRESHOLDS

Condition 6:

TYPICAL MALFUNCTION THRESHOLDS

Condition 7:

TYPICAL MALFUNCTION THRESHOLDS

Condition 8:

TYPICAL MALFUNCTION THRESHOLDS

Case 1:

TYPICAL MALFUNCTION THRESHOLDS

Case 2:

TYPICAL MALFUNCTION THRESHOLDS

Case 3:

TYPICAL MALFUNCTION THRESHOLDS

AIR pressure during AIR ON

Less than 1 kPa and pulse is not generated

AIR pressure during AIR OFF

1 kPa or more and pulse is generated

AIR pressure during AIR OFF

Less than 1 kPa and pulse is generated

AIR pressure during AIR OFF

1 kPa or more and pulse is not generated

AIR pressure during AIR OFF

Less than 1 kPa and pulse is not generated

Any of following conditions met:

(a), (b)or (c)

(a) Conditions 1 and 6

Met

(b) Conditions 1 and 5

Met

(c) Conditions 2 and 6

Met

Any of following conditions met:

(a), (b)or (c)

(a) Conditions 3 and 7

Met

(b) Conditions 3 and 8

Met

(c) Conditions 4 and 8

Met

Cumulative pressure pulsation

75 kPa or more

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

MONITOR RESULT

Refer to CHECKING MONITOR STATUS .

WIRING DIAGRAM

Refer to DTC P0412 .

INSPECTION PROCEDURE

HINT:

Determination by ECM monitoring:

The ECM locates malfunctions in the Secondary Air Injection (AIR) system by detecting the pressure in the
AIR passage between the air pump and Air Switching Valve (ASV) and sets a DTC. Soon after cold engine
starts, the monitor runs for a short time while the AIR system is both ON and OFF. The ECM detects both the
pressure and the exhaust pulsation and compares them.

The following 4 patterns are AIR system pressure conditions in the AIR system passage.

Pressure Condition in Secondary Air Injection System Case 1:

AIR SWITCHING VALVE CONDITION CHART

Pressure Condition in Secondary Air injection System Case 2:

AIR SWITCHING VALVE CONDITION CHART

Pressure Condition in Secondary Air Injection System Case 3:

AIR SWITCHING VALVE CONDITION CHART

Air Pump

ON

Air Switching Valve

Open

Pressure

1 kPa or more

Pulsation Detection

Exhaust gas pulsation detected

Air Pump

OFF

Air Switching Valve

Open

Pressure

Less than 1 kPa

Pulsation Detection

Exhaust gas pulsation detected

Air Pump

ON

Air Switching Valve

Closed

Pressure

1 kPa or more

Pulsation Detection

Slight pulsation detected

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra