Nissan Sentra Service Manual: Exhaust valve timing control

EXHAUST VALVE TIMING CONTROL : System Description

SYSTEM DIAGRAM

INPUT/OUTPUT SIGNAL CHART

SYSTEM DESCRIPTION

This engine is equipped with an exhaust valve timing controller (integral with cam sprocket) which continuously adjusts the phase of intake valve according to driving conditions, improves both low/mid range engine torque and high-speed range engine output, and brings about low emission and low fuel consumption.

The exhaust valve timing control system continuously controls cam phases in constant exhaust valve operating angle conditions and adjusts an operating oil pressure to the exhaust valve timing controller via the control solenoid valve.

ECM receives exhaust valve timing control position signal, crankshaft position signal, engine speed signal, engine oil temperature signal, and engine coolant temperature signal. And the ECM outputs ON/OFF pulse duty signals to the exhaust valve timing control solenoid valve depending on driving status.

Exhaust Valve Timing Controller Operation List

EXHAUST VALVE TIMING CONTROL FEEDBACK CONTROL

Cam Position Detection

The exhaust valve control position sensor mounted at the rear of the cylinder head detects a cam position, by using the groove on the plate located at the rear of the intake camshaft.

Feedback Control

The exhaust valve control position sensor feeds back an actual cam position signal to ECM. Based on the signal, ECM controls the exhaust valve timing control solenoid valve to satisfy the optimum target valve opening/ closing timing according to a driving condition.