P0276 — Cylinder 6 Injector Circuit Low

powertrain (engine/transmission)

Is it safe to drive?

Drive cautiously if stable; repair promptly P0276 can prevent proper fuel delivery to cylinder 6, causing a misfire, rough running, and possible catalyst damage. A short low-speed trip may be reasonable if the engine runs steadily, but avoid sustained or high-load driving and stop if it stalls, misfires severely, smells of fuel, or shows additional warning indicators.

Typical symptoms

  • The check-engine light may illuminate with P0276 stored in the controller
  • Rough, uneven, or unstable idle operation
  • Hesitation or stumble when accelerating
  • A cylinder 6 misfire may appear in OBD2 live data or on a combustion test
  • Noticeable loss of engine power or increased fuel consumption
  • The engine may stutter, stall, or enter a crank-and-run condition in severe cases

Common causes

  • An open break in the power, control, or ground wire leading to the cylinder 6 injector
  • Insulation damage allowing the cylinder 6 injector circuit to short to ground
  • A corroded, loose, bent, or water-contaminated cylinder 6 injector connector terminal
  • An internally open or ground-shorted cylinder 6 injector winding
  • Intermittent loss of power or a poor ground at the ECM/PCM or fuel-injection driver circuit
  • A failed switched-output transistor or internal driver fault in the ECM/PCM

How to diagnose with an OBD scanner

  1. Confirm P0276 and capture operating data Connect an ELM327-based OBD scanner or use AIScanAuto if it supports the required functions. Read stored, pending, and permanent codes, confirm P0276, and save freeze-frame data such as engine speed, load, and cylinder 6 misfire counts.
  2. Inspect the cylinder 6 injector connector and harness With the engine cool and electrical power disconnected, inspect the cylinder 6 injector plug for corrosion, water, loose terminals, damaged locks, and pushed-back pins. Follow the harness toward the ECM/PCM and look for chafing, melting, pinching, or a disconnected ground near hot exhaust components.
  3. Test the injector circuit while it is commanded Use the service wiring diagram to identify the injector terminals, then back-probe the circuit during cranking or running. Check commanded voltage, current or waveform, and voltage drop using the manufacturer procedure. A key-on-only voltage check can miss an open circuit because the controller may not command the injector until startup.
  4. Isolate the injector from the wiring Perform the specified current, waveform, or resistance test and compare the cylinder 6 injector with an adjacent injector where appropriate. A controlled cylinder-to-cylinder substitution may be used only if service information permits it; determine whether P0276 follows the injector or remains on cylinder 6.
  5. Verify module power, grounds, and driver output If the injector and external wiring pass inspection, verify battery voltage, module grounds, connector pin condition, and the injector command waveform at the ECM/PCM. Driver or internal module failure should be considered only after the connector, harness, ground, and injector have been tested.

Approximate repair cost

Typical independent-shop work for P0276 is approximately $250-$1,200 for diagnosis plus injector, connector, or wiring repair. ECM/PCM driver repair or replacement can raise the total above $1,500. Figures are estimates and vary by region, vehicle, and labor rates.

Common questions

What does P0276 mean for cylinder 6?

P0276 means the controller detected an abnormally low signal in the cylinder 6 injector circuit, so fuel delivery to that cylinder may be missing or improperly controlled.

Can I drive with P0276?

If the engine runs steadily, only a short trip may be reasonable, but continued P0276 operation can worsen misfire, fuel consumption, emissions, and catalyst condition.

Does P0276 always mean the injector is bad?

No. P0276 can also result from an open or shorted wire, a corroded connector, a poor ground, or an ECM/PCM driver fault, so testing is required before replacing the injector.

How is the low cylinder 6 injector circuit found?

Use the wiring diagram to check the cylinder 6 injector while it is commanded, measuring voltage, current, waveform, and voltage drop. The circuit must be tested during cranking or running rather than only with the key on.

P0276 is a powertrain diagnostic trouble code that specifically points to an electrical problem with the fuel injector for cylinder 6. When the engine control module (ECM) or powertrain control module (PCM) detects that the voltage on the injector circuit for this cylinder stays abnormally low — essentially sitting near ground potential when it should be switching between 12 volts and ground — it flags P0276 and illuminates the check engine light. The code belongs to the P0200 family of injector circuit malfunctions, which cover various electrical faults in the fuel injection system.

Modern engines rely on precise, pulsed electrical signals to fire each fuel injector at exactly the right moment. Each cylinder has its own dedicated injector, and the control module constantly monitors the circuit for each one. Cylinder 6 is identified according to the manufacturer's firing order — on inline engines it is typically the sixth cylinder from the front, while V-type engines follow a different numbering convention that varies by make. The physical location of cylinder 6 matters during repair because some engines require removing the intake manifold to access it, which adds labor time and cost.

The control module does not set P0276 after a single bad reading. It must observe the low-voltage condition persist across multiple drive cycles under specific operating conditions before activating the malfunction indicator lamp. The freeze frame data stored alongside P0276 is critical — it records engine load, RPM, coolant temperature, and vehicle speed at the moment the fault was detected, allowing you to reproduce those exact conditions during testing.

Common symptoms of P0276

  • Rough idle and noticeable hesitation during acceleration
  • Difficulty starting the engine or extended cranking time
  • Noticeable loss of power when the engine is under load
  • Fuel odor, particularly in more severe cases
  • Increased fuel consumption compared to normal driving
  • In some cases, engine stalling or rough running that worsens over time

What causes P0276?

The most frequent cause is a failed fuel injector on cylinder 6 that has an internal electrical fault dragging the circuit low. A chafed or broken wire in the signal circuit can also short directly to ground. Other common culprits include a lack of supply voltage reaching the injector due to a power relay issue or wiring problem, a weak or failing fuel pump unable to maintain adequate rail pressure, and a clogged fuel filter restricting fuel flow to the injectors. Contaminated fuel or incorrect fuel type can also affect injector performance and trigger this code. A faulty fuel rail pressure sensor may send incorrect data to the control module, causing it to misinterpret injector circuit behavior.

How to diagnose P0276

  1. Connect an OBD2 scanner and confirm P0276 is stored in the ECM/PCM memory. Save the freeze frame data immediately — this snapshot of engine conditions when the fault occurred is essential for recreating the problem during testing.

  2. Scan for any other diagnostic trouble codes. Related codes often point to the underlying cause, whether it is an electrical short, a fuel pressure issue, or a sensor malfunction. Also check for manufacturer technical service bulletins (TSB) specific to your vehicle make and model — many common P0xxx codes have published factory fixes or software updates that resolve the issue without part replacement.

  3. Perform a thorough visual inspection of the wiring harness and connectors serving the fuel injection system. Look for damaged insulation, exposed wires, corrosion at the connector terminals, and any signs of chafing where the harness passes near metal edges or heat sources.

  4. Check for proper supply voltage at the cylinder 6 injector connector using a multimeter. Then measure resistance from the signal wire to ground — a reading near zero ohms confirms a short to ground somewhere in the harness that must be located and repaired.

  5. Measure fuel pressure at the fuel rail with the engine running at idle and under simulated load conditions. Compare the readings against the factory specification for your vehicle — low pressure indicates a fuel supply problem such as a weak pump, clogged filter, or failing pressure regulator.

  6. After repairs are completed, clear the code and perform a complete drive cycle that includes the specific conditions captured in the freeze frame data. Verify that P0276 does not return and that the engine runs smoothly across all operating conditions.

Repair options and costs

Once the faulty component has been identified through proper diagnosis, repair costs (parts and labor, USD, at independent shop rates) typically fall within these ranges:

  • Replace the fuel pressure regulator or fuel rail pressure sensor: $150–$450
  • Replace the fuel pump: $400–$900
  • Clean or replace the fuel injectors: $200–$800
  • Replace the fuel filter: $80–$200

Overall, addressing P0276 usually costs between $80 and $900 depending on which part has failed. Proper diagnosis before purchasing replacement parts is essential to avoid unnecessary expense — the most expensive repair scenario is rarely the first place to look.

Can you drive with P0276?

Drive with caution. A cylinder 6 injector circuit low condition disrupts fuel delivery to one cylinder, causing misfires, rough running, hesitation, and increased emissions. In traffic situations this can lead to stalling or loss of power at dangerous moments. Severe cases allow unburned fuel to enter the exhaust stream, potentially damaging the catalytic converter. Avoid long trips and have the vehicle diagnosed and repaired promptly.