What it means
The control module detects a circuit-high condition in the air-assisted injector control circuit.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
On engines equipped with air-assisted injection, a control circuit operates the valve or solenoid that directs air to help atomize fuel at the injectors. P0067 sets when the control module detects that circuit's signal above the expected range, which can result from a short to battery voltage or damaged wiring.
Common causes
Most likely first.
- Wiring shorted to battery
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check-engine light on
- Rough idle
- Hesitation or reduced acceleration
- Engine may run poorly
How to diagnose it
- Record freeze-frame data and check for related injector or air-assist codes to see whether the high signal coincides with poor running.
- Inspect the air-assist control valve or solenoid connector and harness for pin damage, chafing, or contact with a B+ wire.
- Using the wiring diagram, check for an unintended connection to battery voltage and inspect connector terminals for corrosion.
- Disconnect the control device and test circuit continuity and for shorts to power, following the manufacturer's procedure.
- If the wiring and device pass, test the control circuit output according to the manufacturer's diagnostic procedure.
Common fixes
- Repair a pinched or chafed air-assist control wire shorted to battery voltage.
- Clean or repair damaged or corroded connector terminals.
- Replace a failed air-assist control valve or solenoid if testing confirms it.
- Repair a confirmed circuit or module control fault.
Can I keep driving?
If the engine runs poorly or hesitates, avoid hard acceleration and limit driving until the fault is checked. The air-assist system may not control fuel atomization correctly, worsening drivability and emissions.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.