VARIABLE TUMBLE CONTROL SYSTEM (VTCS) [LF, L3]

id0140001766a6

Outline

• The VTCS actuates the VTCS shutter valve in the intake manifold to increase the intake air flow speed and create tumbling air in the combustion chamber for better atomization of injected fuel, thus reducing the HC and CO exhaust emissions at light loads.

Operation Conditions

• The PCM turns the VTCS solenoid valve on to close the VTCS shutter valve in the intake manifold when all of the following conditions are met:

- Engine speed: below 3,750 rpm

- Throttle opening angle is according to the following:

Below 1,500 rpm: CTP

Between 2,000 rpm and 3,000 rpm: 26-29%

Above 2,500 rpm: WOT

- ECT below 63 °C {145 °F}

• The PCM turns the VTCS solenoid valve off to maintain startability and stability during the engine cranking and for 0.2 second after the engine is started.