P0066 Fault Code

Air Assisted Injector Control Circuit or Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

P0066 is a generic fault code that indicates a problem with the air assisted injector control circuit or circuit low. This code is typically found in vehicles equipped with air assisted injectors, which are devices used to introduce additional air into the intake manifold for better fuel atomization and combustion.

The control circuit of the air assisted injector includes the wiring, connectors, and the injector itself. When the Powertrain Control Module (PCM) detects that the voltage in the air assisted injector control circuit is too low, it triggers the P0066 code, indicating a potential issue in the circuit.

There are several potential causes for this fault code, including:

1. Faulty air assisted injector: The injector itself may be malfunctioning, not allowing enough air to enter the intake manifold.

2. Wiring or connector issues: Damaged or loose wiring connections can cause low voltage in the circuit.

3. Problems with the PCM: A faulty PCM may not be properly controlling the air assisted injector circuit.

To diagnose and resolve the P0066 code, the following steps can be taken:

1. Visual Inspection: Check for any damaged wiring or loose connections related to the air assisted injector circuit.

2. Test the air assisted injector: Use a multimeter to measure the resistance of the injector. If it's out of specification, the injector should be replaced.

3. Test the wiring and connectors: Inspect the wiring and connectors for any signs of damage, corrosion, or poor connections. Repair or replace as necessary.

4. PCM testing: If all other components are functioning correctly, it may be necessary to test the PCM to ensure it is functioning properly. This typically requires specialized diagnostic equipment and knowledge.

After taking these steps, it is necessary to clear the fault code and perform a test drive to see if the issue has been resolved. If the problem persists, further diagnosis may be required.

It's important to note that the specific diagnostic and repair procedures can vary depending on the make, model, and year of the vehicle. Consulting the vehicle's service manual or seeking assistance from a qualified mechanic is recommended for an accurate diagnosis and proper repair.

What are the symptoms of the P0066 code?

The P0066 fault code is related to the air assisted injector control circuit or circuit low. Some possible symptoms of this fault code on cars may include:

• Check Engine Light (MIL) illuminated
• Decreased engine performance or power
• Rough idling or stalling
• Poor fuel economy
• Difficulty starting the engine
• Increased exhaust emissions

It is important to note that these symptoms may vary depending on the specific make and model of the vehicle. Consulting with a professional mechanic or using a reliable OBD-II scanner is recommended for an accurate diagnosis and repair.

What causes the P0066 code?

The P0066 fault code indicates a problem with the air-assisted injector control circuit or circuit low. Some possible causes for this error code include:

1. Malfunctioning air-assisted injector control solenoid.
2. Faulty wiring or connectors in the air-assisted injector control circuit.
3. Low voltage or a short circuit in the circuit.
4. Issues with the powertrain control module (PCM).

If you encounter this fault code, it is recommended to consult a qualified mechanic or use a diagnostic tool to further diagnose and determine the specific cause of the issue.

How to fix P0066?

To fix the P0066 fault code on cars, you can follow these steps:

1. Check the air assisted injector control circuit for any loose or damaged connections. Inspect the wiring and connectors for signs of corrosion or damage. Repair or replace any faulty components as necessary.

2. Test the air assisted injector control circuit using a multimeter. Measure the voltage at the circuit and compare it to the specifications provided by the manufacturer. If the voltage is below the specified range, there may be a problem with the circuit.

3. Inspect the air assisted injector for any clogs or blockages. Clean or replace the injector if necessary.

4. Check the air intake system for any leaks or restrictions. Repair or replace any damaged components.

5. Clear the fault code using a diagnostic scan tool. If the fault code returns after clearing it, there may be an ongoing issue that needs further diagnosis.

6. If necessary, seek assistance from a professional mechanic or dealership for further diagnosis and repair.

Note: It is important to refer to the specific repair manual or manufacturer's instructions for your car model for accurate and detailed instructions.