P0067 — Problem with air-assisted injector electrical circuit

The engine control module detected an electrical issue in the air-assisted fuel injector circuit, usually meaning a voltage is higher than expected. This can cause poor fuel delivery or engine performance problems. It often happens due to wiring faults, connector issues, or a failing injector control component.

Common causes

The cause is almost always one of a few things. Here they are — P0067 rarely comes from anything outside this list:

• Damaged or corroded wiring in injector circuit
• Loose or faulty electrical connector at injector
• Faulty air-assisted injector control valve
• Engine control module malfunction
• Short circuit or open circuit in wiring harness

Where to start

In the order a sensible mechanic would work — the cheap checks first, the expensive replacements only after:

1. Inspect and clean injector electrical connectors
2. Check wiring harness for damage or corrosion
3. Test injector control valve operation
4. Replace faulty injector control valve if needed
5. Diagnose and repair or replace engine control module as last resort

That is what holds for P0067 in general. From here it depends on your engine — tell me which car it is and what it does, and I will give you the steps for it: real procedures, torque figures and diagrams instead of general advice.