Honda Element. Manual — part 535

Fig. 33: Sectional View Of Manifold Absolute Pressure (MAP) Sensor
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Mass Air Flow (MAF) Sensor/Intake Air Temperature (IAT) Sensor

The mass airflow (MAF) sensor/intake air temperature (IAT) sensor contains a hot wire and a thermistor. It is
located in the intake air passage. The resistance of the hot wire and thermistor change due to intake air
temperature and air flow. The control circuit in the MAF sensor controls the current to keep the hot wire at a set
temperature. The current is converted to voltage in the control circuit, then output to the ECM/PCM.

Fig. 34: Sectional View Of Mass Air Flow (MAF) Sensor/Intake Air Temperature (IAT) Sensor
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Output Shaft (Countershaft) Speed Sensor

This sensor detects output shaft (countershaft) speed.

2007 Honda Element EX

2007-2008 ENGINE PERFORMANCE Fuel and Emissions Systems - Element

Fig. 35: Sectional View Of Output Shaft (Countershaft) Speed Sensor
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Secondary Heated Oxygen Sensor (Secondary HO2S)

The secondary HO2S detects the oxygen content in the exhaust gas downstream of the three way catalytic
converter (TWC), and sends signals to the ECM/PCM which varies the duration of fuel injection accordingly.
To stabilize its output, the sensor has an internal heater. The ECM/PCM compares the HO2S output with the
A/F sensor output to determine catalyst efficiency. The secondary HO2S is located on the TWC.

Fig. 36: Sectional View Of Secondary Heated Oxygen Sensor (Secondary HO2S)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

ELECTRONIC THROTTLE CONTROL SYSTEM

The throttle is electronically controlled by the electronic throttle control system. Refer to the SYSTEM
DIAGRAM to see a functional layout of the system.

Idle control: When the engine is idling, the ECM/PCM controls the throttle actuator to maintain the proper idle
speed according to engine loads.

Acceleration control: When the accelerator pedal is pressed, the ECM/PCM opens the throttle valve depending
on the accelerator pedal position (APP) sensor signal.

2007 Honda Element EX

2007-2008 ENGINE PERFORMANCE Fuel and Emissions Systems - Element

Cruise control: The ECM/PCM controls the throttle actuator to maintain set speed when the cruise control is
operating. The throttle actuator takes the place of the cruise control actuator.

Accelerator Pedal Position (APP) Sensor

As the accelerator pedal position changes, the sensor varies the signal voltage to the ECM/PCM.

Fig. 37: Sectional View Of Accelerator Pedal Position (APP) Sensor
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Throttle Body

The throttle body is a single-barrel side draft type. The lower portion of the throttle valve is heated by engine
coolant from the cylinder head to prevent icing of the throttle plate.

2007 Honda Element EX

2007-2008 ENGINE PERFORMANCE Fuel and Emissions Systems - Element

Fig. 38: Identifying Throttle Body
Courtesy of AMERICAN HONDA MOTOR CO., INC.

VTEC/VTC



The i-VTEC has a VTC (variable valve timing control) mechanism on the intake camshaft in addition to
the usual VTEC.

This mechanism improves fuel efficiency and reduces exhaust emissions at all levels of engine speed,
vehicle speed, and engine load.



The VTEC mechanism changes the valve lift and timing by using more than one cam profile.



The VTC changes the phase of the intake camshaft via oil pressure. It changes the intake valve timing
continuously.

2007 Honda Element EX

2007-2008 ENGINE PERFORMANCE Fuel and Emissions Systems - Element