P0067 – Air Assisted Injector Control Circuit High
The P0067 diagnostic trouble code indicates that the Engine Control Module (ECM) has detected a high voltage condition in the Air Assisted Injector Control circuit. This system is used on certain vehicles to improve fuel atomization by supplying pressurized air to the fuel injectors, helping enhance combustion efficiency and reduce emissions.
When the ECM detects voltage above the expected range in the control circuit, it stores the P0067 code and turns on the Check Engine Light.
Common Symptoms
- Check Engine Light ON
- Rough idle
- Reduced engine performance
- Increased fuel consumption
- Higher exhaust emissions
Common Causes
- Faulty air-assisted injector control solenoid
- Short to battery voltage in the control circuit
- Damaged wiring or connector
- Poor electrical connection
- Rarely, a faulty ECM
Basic Diagnosis
Inspect the wiring harness and connectors for damage, verify the power supply and ground, check for a short to battery voltage, and use a scan tool to command the air-assisted injector system. Repair wiring faults or replace the faulty solenoid if required.
Diagnostic Note: The Air Assisted Injector system is not equipped on all vehicles. Component locations, wiring configurations, and diagnostic procedures vary between manufacturers. Always consult the factory service manual and wiring diagram before testing.