Thermostat Housing
Engine Valve Cove
Intake Manifold
Expansion Tanks
Variable Valve Timing (VVT)

EGR Valve
Secondary Air Pump
Oil Cooler
Blower Resistor
Heater Valve
Throttle Body
Ignition Coil
Nitrogen Oxygen Sensor
Headlight Leveling Sensor
Oxygen Sensor
Temperature Sensor
Brake Light Switch
Fuel Pressure Regulator
Mass Air Flow Sensor
Oil Pressure Switch
ABS Sensor
Auxlliary Water Pump

Variable Valve Timing (VVT) Solenoid (timing control solenoid)

What They Do
Variable ValveTiming (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems. There are many ways in which this can be achieved, ranging from mechanical devices to electro-hydraulic and camless systems. Increasingly strict emissions regulations are causing many automotive manufacturers to use VVT systems.

Failure Symptoms
---Check Engine Light comes on. Since today's modern cars are controlled by an Engine Control Unit (ECU), virtually all individual components are monitored by the ECU. ...
---Engine oil is dirty. This is more of a cause as opposed to a symptom. ...
---Rough engine idle. ...
---Decrease?in fuel economy.