What is an air intake valve?

An idle air control actuator or idle air control valve (IAC actuator/valve) is a device commonly used in fuel-injected vehicles to control the engine’s idling rotational speed (RPM).

One of the most common symptoms associated with a problematic idle air control valve is irregular idle speed. 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.

Subsequently, question is, what is the function of idle air control valve? An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone]. This causes the idling speed of the engine to change as needed.

Moreover, how do you know if the idle air control valve is bad?

Method 1 Identifying Issues with an Idle Control Valve

  1. Look for a high engine idle. A common symptom of a faulty idle control valve can be a high idle.
  2. Pay attention to low idle or stalling.
  3. Look for signs of a vacuum leak.
  4. Take note if the check engine light comes on.

How do I reset my idle air control valve?

Reset the IAC valve pintle position by performing the following:

  1. Depress the accelerator pedal slightly.
  2. Start the engine and run for 5 seconds.
  3. Turn the ignition switch to the OFF position for 10 seconds.
  4. Restart the engine and check for proper idle operation.

Can you drive with a bad IAC valve?

Can a bad IAC valve cause the engine to miss at driving speeds? No. It will handle larger idle changes such as when the vehicle is in drive but the vehicle is not moving because you had the brake pedal on. The idle air control will speed the engine up to compensate for that load.

How much does it cost to fix an idle air control valve?

When the engine is cold, the IAC valve helps to get it started. If it breaks down on you or starts to malfunction, then you are going to have to get it replaced. The cost of that, on average, will be between $115 and $500. You will likely pay about $70 for labor and anywhere from $45 to just over $400 for parts.

Where is idle control valve located?

The idle air control valve (IAC) is located near the throttle body of the intake manifold in most cases. Additional designs include rubber hoses running from the throttle body and air intake tube to a remote valve.

Can idle air control valve be cleaned?

Cleaning an idle air-control valve can keep you from buying a new part, but only certain idle air-control valves can be cleaned. The idle air-control valve must have a spring-operated valve for cleaning to make it work.

What will a bad throttle position sensor do?

What happens when my throttle position sensor goes bad. When a TPS goes bad, then the car’s throttle body won’t function properly. It could either stay shut or it won’t close properly which is a severe issue. If it stays shut then your engine is not going receive air and it won’t start.

Will a bad IAC cause loss of power?

The same happens with the power steering, which also uses electricity and increases the load in the IAC. Eventually, it will stop working and prevent the engine from working correctly. You may not experience a completely stalled engine, but a significant loss in RPM, which is another clear sign the IAC is faulty.

What happens when the IAC valve goes bad?

One of the most common symptoms commonly associated with a problematic idle air control valve is irregular idle speed. 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.

How do I reset my idle speed?

To reset the IAC valve pintle position proceed as follows: Block the drive wheels, then apply the parking brake firmly. Start the engine, then hold the engine speed above 2,000 rpm. Turn the ignition OFF , then restart the engine and check for proper idle operation.

Where is the throttle position sensor located?

Throttle Position Sensor (TPS) Repair Guide Fig. The Throttle Position (TP) Sensor is located on the rear of the intake manifold. The Throttle Position (TP) Sensor is located on the bulkhead, above the accelerator pedal. The Throttle Position (TP) Sensor is located on the bulkhead, above the accelerator pedal.

How many throttle bodies does a car have?

Most autos have just one large throttle body, but some larger-engined cars can have one for each bank of cylinders, or even one on every cylinder, although these are relatively uncommon.