Fuel and air

P0276 — Cylinder 6 Injector Circuit Low

Severity: medium Drive with care, to a shop

What P0276 means

The engine control module fires the cylinder 6 injector by switching its circuit to ground through a driver, and it monitors the voltage in that circuit. P0276 is set when that voltage is lower than expected. This can come from a short to ground, damaged wiring, a failed injector coil, or a faulty driver inside the ECM.

Symptoms

  • Check Engine Light on
  • Rough idle or engine vibration
  • Loss of power or hesitation on acceleration
  • Increased fuel consumption
  • Cylinder 6 misfire
  • Possible stalling under load

Possible causes

  1. Damaged, chafed, or corroded wiring or connector at the cylinder 6 injector
  2. Faulty cylinder 6 injector (shorted coil)
  3. Short to ground or open circuit in the injector wiring
  4. Failed injector driver inside the ECM
  5. Blown fuse or faulty relay supplying injector power

How to diagnose

  1. Scan for codes and freeze frame data, and note any other injector or misfire codes
  2. Inspect the cylinder 6 injector connector and harness for rubbing, melting, corrosion, or moisture
  3. Check the injector fuse and relay
  4. Measure injector coil resistance and compare with spec or with the other injectors
  5. Check for power at the connector and test the wires for a short to ground
  6. Swap the injector with a neighboring cylinder and see whether the fault follows it
  7. Check the ECM control pulse with a scope or noid light
  8. Review fuel trims and cylinder balance, and check fuel pressure

Common fixes

  • Repair or replace damaged wiring and connectors
  • Replace the faulty cylinder 6 injector
  • Replace a blown fuse or bad relay
  • Repair or replace the ECM if the driver is confirmed faulty

Questions and answers

What does P0276 mean?

The engine computer detected low voltage in the cylinder 6 injector circuit. Wiring, the connector, or the injector itself are the most common culprits.

Can I drive with P0276?

Briefly and carefully, yes, but the engine will run rough and lose power. Don't put off the repair, since misfires can damage the catalytic converter.

How do I tell a bad injector from a wiring problem?

Measure the injector resistance and inspect the harness. If swapping the injector with a neighbor moves the fault to that cylinder, the injector is bad; if not, suspect the wiring or the ECM.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.