P0268
UniversalCylinder 3 Injector Circuit High
Medium SeverityThis code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the circuit for the Cylinder 3 fuel injector. This can lead to the injector not operating correctly, causing engine misfires and drivability issues.
⚠️ Before You Begin (Safety First)
Always ensure the engine is off and cool before working on any engine components. Disconnect the battery's negative terminal to prevent electrical shocks or accidental starts. Be cautious around fuel lines as fuel is flammable.
Common Symptoms
- Check Engine Light illuminated
- Engine misfire
- Rough idle
- Poor acceleration
- Reduced fuel economy
- Engine hesitation or stalling
Common Causes
- Faulty Cylinder 3 fuel injector
- Open or short in the fuel injector wiring harness
- Corroded or loose connector at the injector or PCM
- Faulty Powertrain Control Module (PCM)
- Wiring shorted to voltage source
Frequently reported on: General/Universal
Diagnostic Steps
- Visually inspect the wiring and connector for the Cylinder 3 fuel injector for any obvious damage, corrosion, or loose connections. Make sure the connector is securely seated.
- If accessible, disconnect the injector connector and check the resistance of the Cylinder 3 fuel injector using a multimeter. Compare it to specifications or other injectors.
- If the injector tests good, inspect the wiring harness for continuity and for any shorts to ground or power between the injector connector and the PCM connector.
- Consider swapping the Cylinder 3 injector with an injector from another cylinder (if easily accessible and identical) to see if the code moves to the new cylinder location, indicating a faulty injector.
👨🔧 When to Call a Professional
If you have checked the wiring and connector for the Cylinder 3 fuel injector and have confirmed the injector itself is good, but the code persists, it's time to consult a professional. Advanced diagnostics may be needed to check the PCM or underlying electrical issues.
Commonly Asked Questions
What does 'Injector Circuit High' mean?
It means the computer detected an electrical voltage in the fuel injector circuit for cylinder 3 that is higher than expected, suggesting a wiring issue or a problem with the injector itself.
Can I drive with a P0268 code?
Driving with this code can lead to engine misfires, reduced power, and poor fuel economy. It's best to address it promptly to prevent potential damage to other engine components like the catalytic converter.
How do I locate Cylinder 3?
Cylinder numbering varies by manufacturer. For inline engines, it's usually 1, 2, 3... from front to back. For V-engines, consult your vehicle's service manual or an online diagram for your specific make and model.
Is it possible for a bad PCM to cause this code?
Yes, although less common than wiring or injector issues, a faulty Powertrain Control Module (PCM) could send incorrect voltage or fail to interpret the circuit correctly, leading to a P0268 code.