What is ISC in a car?
The Idle Speed Control (ISC) valve, also called an Idle Air Control (IAC) valve, is used on both throttle body and multipoint fuel injected engines to regulate idle speed. The ISC valve is controlled by the engine’s computer (powertrain control module or PCM).
How does the idle speed control actuator work?
An idle speed control actuator is controlled by an idle speed control actuator solenoid. This solenoid is controlled by a control module. When this solenoid is turned off, no vacuum is routed to the idle speed control actuator, allowing it to open the throttle slightly to increase idle speed.
What happens if the idle speed control valve goes bad?
If there was no idle speed control valve, then your engine would just stall every time you stop the vehicle. By having a fully functional idle speed control valve, the engine idle speed never goes below 900 RPM or above 1,100 RPM. If you have an idle speed control valve which is starting to go bad, then you need to replace it as soon as possible.
What does the idle air control valve do?
Its purpose is to control and regulate the engine idle speed, increasing and decreasing it as necessary to keep up with operating conditions. If the engine control module detects an issue with the idle air control valve circuit or signal, it will set off the Check Engine Light to notify the driver that there’s an issue.
What causes the idle speed to go up or down?
The idle air control valve is programmed to regulate and maintain the engine idle speed at a constant rate. If the valve fails or has any issues it can cause the idle speed to be thrown off. This may result in an unusually high or low idle speed, or in some cases a surging idle speed that repeatedly climbs and falls. 2. Check Engine Light comes on
How does the idle speed control system work?
Idle speed control system. In addition, the digital engine control system receives digital on/off status inputs from several power-consuming devices attached to the engine, such as the air-conditioner clutch switch, park-neutral switch, and the battery charge indicator. These inputs indicate the load that is applied to the engine during idle.
What are the symptoms of bad idle speed control valve?
Below are the top 5 symptoms of a bad idle speed control valve. 1) Stalled Engine – A bad idle speed control valve will cause your engine to stall. Depending on the extent of the wear or damage to the valve, the engine will stall immediately after you start the car. Either that or it will stall after a couple of minutes.
What should I do if my idle control motor is disconnected?
The engine should still start and run without any issue despite the idle control motor being disconnected. Be sure to tuck the wiring you disconnected up in the engine bay so it doesn’t get caught in any moving parts. Look for a difference in idle speed.
When does the Idle Control System Trigger p0507?
The standard RPM per vehicle varies depending on make and model, but most engines should ideally run between 600 and 800 RPM while idling. For example, some GM vehicles will trigger code P0507 if the engine computer clocks an idle speed that is 200 RPM above the recommended range.