Acura RL. Manual - part 67

Fig. 222: Intake Manifold Tuning Sensor Output Characteristics 

General Description 

The intake manifold tuning (IMT) system controls engine output by selecting either long or short intake 
runner lengths. The system consists of the IMT valve, the IMT actuator, and the powertrain control module 
(PCM). The IMT actuator is attached to the intake manifold and it includes the motor and the Hall-effect-IC 
position sensing unit. The PCM actuates the motor, which operates the IMT valve. When the IMT valve is 
closed, the long runner is selected, increasing torque at low engine speed. When the IMT valve is open, the 
short runner is selected, increasing torque at high engine speed. A Hall-effect-IC position sensing unit is 
integrated with the motor to provide precise open/close feedback to the PCM. The IMT actuator sends a 
long runner return signal to the PCM when the IMT valve is closed, and it sends a short runner return signal 
when the IMT valve is open. 

If the PCM receives no closed return signal when it sends a close command, or if it receives no open return 
signal when sending an open command to the IMT actuator, for a specified time, it detects a malfunction 
and stores a DTC. 

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

MONITOR DESCRIPTION CHART 

Execution

Once per driving cycle

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

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Enable Conditions 

ENABLE CONDITIONS 

Malfunction Threshold 

When the PCM sends an open (short runner) command, no short runner return signal is received for at least 
3 seconds. 

Driving Pattern 

1. Start the engine. Let it idle until the radiator fan comes on.  

2. Hold the engine speed to 4,000 rpm or more for at least 3 seconds.  

Diagnosis Details 

Conditions for illuminating the MIL 

When a malfunction is detected during the first drive cycle, a Temporary DTC is stored in the PCM 
memory. If the malfunction recurs during the next (second) drive cycle, the MIL comes on and the DTC and 
the freeze frame data are stored. 

Conditions for clearing the MIL 

The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the 
diagnostic runs. 

The MIL, the DTC, the Temporary DTC, and the freeze frame data can be cleared by using the scan tool 
Clear command or by disconnecting the battery. 

DTC P1109 (13): ADVANCED DIAGNOSTICS 

DTC P1109: BAROMETRIC PRESSURE (BARO) SENSOR CIRCUIT OUT OF RANGE-HIGH 

Sequence

None

Duration

3 seconds or more

DTC Type

Two drive cycles, MIL ON

OBD Status

PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Condition

Minimum

Maximum

Intake air temperature

5°F (-15°C)

-

Engine speed

4,000 rpm

-

Battery voltage

10.5 V

-

No active DTCs

P0107, P0108, P0112, P0113, P0117, P0118, P0563, P1109, 
P1128, P1129, P2227, P2228, P2229

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

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Fig. 223: Barometric Pressure Sensor Circuit Diagram 

Fig. 224: Barometric Pressure Sensor Output Voltage Graph 

General Description 

The barometric pressure (BARO) sensor is built into the powertrain control module (PCM) and monitors 
atmospheric pressure. The PCM estimates appropriate intake airflow from the manifold absolute pressure 
(MAP) sensor output voltage and BARO sensor output voltage. When BARO sensor output voltage is 
within the specified range, a malfunction is detected and a DTC is stored. 

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

MONITOR DESCRIPTION CHART 

Enable Conditions 

Execution

Continuous

Sequence

None

Duration

2 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:06 PM

Page 267  © 2005 Mitchell Repair Information Company, LLC. 

ENABLE CONDITIONS 

Malfunction Threshold 

The BARO sensor output voltage is between 3.59 V to 4.49 V for at least 2 seconds. 

Diagnosis Details 

Conditions for illuminating the MIL 

When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the 
PCM memory. 

Conditions for clearing the MIL 

The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the 
diagnostic runs. 

The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by 
disconnecting the battery. 

DTC P1116 (86): ADVANCED DIAGNOSTICS 

DTC P1116: ENGINE COOLANT TEMPERATURE (ECT) SENSOR 1 PERFORMANCE 
PROBLEM 

Condition

 

Ignition switch

ON

No active DTCs

P2228, P2229

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:06 PM

Page 268  © 2005 Mitchell Repair Information Company, LLC.