System Description
| Sensor | Input signal to ECM | ECM function | Actuator | ||
|---|---|---|---|---|---|
| Crankshaft position sensor (POS) | Engine speed(1) | Tumble control valve control | Tumble control valve motor | ||
| Camshaft position sensor (PHASE) | |||||
| Battery | Battery voltage(1) | ||||
| Engine coolant temperature sensor | Engine coolant temperature | ||||
| Accelerator pedal position sensor | Accelerator pedal position | ||||
| Tumble control valve position sensor | Tumble control valve position | ||||
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Tumble control valve has a valve portion in the intake passage of each cylinder.
While idling and during low engine coolant temperature, the tumble control valve closes. Thus the velocity of the air in the intake passage increases, promoting the vaporization of the fuel and producing a tumble in the combustion chamber.
Because of this operation, this system tends to increase the burning speed of the gas mixture, improve fuel consumption, and increase the stability in running conditions.
Also, except when idling and during low engine coolant temperature, this system opens the tumble control valve.
In this condition, this system tends to increase power by improving intake efficiency via reduction of intake flow resistance.
The tumble control valve is operated by the ECM.