Diagnostic guide for OBD-II code P0292

Cylinder 11 Injector Circuit High

Code description and context

• Code meaning [Open Source definition].
  • Source note: Open Source entry explicitly labels this as "Cylinder 11 Injector Circuit High." See the injector circuit description for cylinder 11.
  • Related reference: OBD-II concepts and powertrain codes are summarized in Wikipedia's OBD-II sections on Diagnostic Trouble Codes and Powertrain Codes, which describe how DTCs are generated and organized within the Powertrain system.

Symptoms

• Check Engine light (MIL) is on.
• Misfire symptom localized to cylinder 11 (engine may run rough, especially under load or at idle).
• Reduced engine power or acceleration when the issue is present.
• Rough idle or fluctuating idle quality.
• Possible decrease in fuel economy.
• You might notice a hard start or hesitation if injector timing or duty is significantly off.
  Note: Some symptoms overlap with other cylinder misfire codes or fuel/sensor faults. Confirm with scan data and tests rather than relying on symptoms alone.

Probable Causes

Because P0292 is an injector-circuit fault for a specific cylinder, the likely root causes generally fall into one of these groups:

• Injector circuit/wiring issues for cylinder 11
  • Damaged, pinched, corroded, or unplugged injector 11 wiring harness and/or connector.
  • Short to power or intermittent high signal on the injector control circuit (PCM output to injector 11).
  • Ground integrity problems in the injector circuit path (intermittent or weak ground reference can manifest as abnormal signaling).
• Faulty injector 11 (hardware inside the injector)
  • Injector 11 coil or internal otvor faults causing abnormal current or driver load.
  • Sticking or partially stuck injector affecting susceptibility to high-side signaling or duty cycle behavior.
• PCM/driver issues
  • Faulty injector drive output in the PCM for cylinder 11 (rare but possible).
  • Software/calibration issue that intermittently drives the 11th injector high or misreads feedback.
• Auxiliary or related fuel-system issues (less common as primary cause, but can affect interpretation)
  • Abnormal fuel pressure or supply conditions that alter injector signal load requirements and trigger control anomalies.
• The exact text for P0292 is listed in the Open Source repository as (Cylinder 11 Injector Circuit High). Use this as the canonical description for this code.

Diagnostic Approach

Prepare safely before starting

• Ensure the vehicle is in a safe, well-ventilated area; engine off, ignition off, and key out to inspect wiring. For electrical tests, follow standard shop safety procedures and use insulated tools and proper PPE.
• Retrieve relevant data with an OBD-II scan tool; note freeze-frame data, misfire history, fuel trim, injector pulse width, and cylinder-specific misfire counts if available.

Step 1: Confirm the code and context

• Confirm P0292 is current (not a pending or history code) and notes cylinder 11 specifically.
• Review freeze-frame data for engine load, RPM, fuel trim (short-term and long-term), and injector pulse width at the time the code was stored.
• Check for related codes (e.g., P030X for misfire on various cylinders, P017X/P018X for fuel trim, or any other injector-related codes) to help triangulate.

Step 2: Visual and mechanical inspection

• Inspect the injector 11 wiring harness and its connector:
  • Look for damaged insulation, worn routing near moving parts, abrasion, or signs of heat.
  • Check for bent, corroded, or loose connector pins.
  • Look for signs of fuel or oil contamination on the connector that could alter signal integrity.
• Inspect related fuel rail and injector mounting hardware for leaks or improper seating.
• Check nearby sensors (e.g., wiring harnesses around the injector harness) for heat or chafing that could affect electrical signals.

Step 3: Electrical measurements and signal validation

• Check injector 11 coil resistance (cold resistance) with a proper multimeter:
  • Compare to the manufacturer's specification in the service manual. An out-of-spec resistance can indicate an internal injector fault.
• Verify the injector control signal (cylinder 11) with a relative signal test:
  • Using a scope or a high-quality oscilloscope/graphing tool, observe the injector control line from the PCM to cylinder 11.
  • Look for a "high" level when the PCM should be pulsing the injector (i.e., the signal should be switching between ground and pulse/off states as commanded). A consistently high signal or a signal that fails to switch can indicate a control-circuit fault.
  • If you don't have an oscilloscope, use a logic probe or diagnostic runtime data if your tool can display injector waveform data.
• Probe for short to power on the injector control wire (without disturbing the circuit) to determine if a hidden short to battery is present.

Step 4: Functional testing and component isolation

• Swap tests (diagnostic swaps) to localize the fault:
  • Swap injector 11 with another cylinder's injector (or swap the wiring harness connectors to the injector for cylinder 11 with cylinder X).
  • After swap, re-run the vehicle and monitor for changes:
    • If the P0292 moves to the other cylinder (e.g., P029X for the new cylinder), the injector itself or its wiring for the original cylinder was the issue.
    • If the code remains P0292 on cylinder 11 despite swapping injectors, the issue is more likely in the wiring, a PCM output, or a software/ECU-side condition rather than the injector itself.
• If you have access to a known-good injector for cylinder 11, install it temporarily to see if the code clears and the misfire symptom improves.

Step 5: Fuel system and related diagnostics

• Check fuel pressure and fuel rail integrity to ensure adequate fuel supply; abnormal pressure can complicate symptoms but is not typically the primary cause of a high injector signal.
• Review engine fuel trim and oxygen sensor readings to ensure there isn't a larger fuel-management issue masking a control-signal fault.
• If misfire is present alongside abnormal fuel trim, consider broader tests for intake leaks, vacuum leaks, or sensor faults that could influence injector timing and control.

Step 6: PCM/driver assessment

• If wiring and injector hardware pass tests and the signal still reads abnormally high, evaluate the injector-driver output and PCM behavior:
  • Verify there isn't a software/firmware issue in the PCM that misinterprets feedback or misdrives a single injector.
  • Consider PCM-related service bulletins or updates from the manufacturer if available.
• In rare cases where the injector drive for cylinder 11 is confirmed faulty and other injectors and circuits test normal, PCM replacement or reprogramming could be considered.

Step 7: After repair, verify and validate

• Reset the DTC memory and perform a road test to verify the fix:
  • Confirm P0292 does not return.
  • Monitor cylinder 11 misfire counter, injector duty cycle, fuel trims, and engine performance during a representative drive cycle.
• Look for no adverse symptoms after the repair, and ensure all related codes are cleared.

Repair Options

• If injector 11 is faulty:

  • Replace injector 11 (or the entire injector assembly as per OEM practice).

• If wiring/connectors are faulty:

  • Repair damaged harness segments, replace connector or pins, ensure proper shielding and routing to prevent future chafing.

• If injector driver/PCM output is at fault:

  • Repair or replace the PCM/DME/ECU per OEM guidance; reprogramming or re-flashing may be required per manufacturer.

• If the injector itself is stuck or leaking:

  • Replace the injector set (or at least the injector), verify seals O-rings, and ensure proper injector flow.

• If fuel-system or sensors contribute to the condition:

  • Address any related fuel-supply issues (pressure, injector cleanliness, fuel filter) and any sensor faults contributing to the misfire.

• The exact code P0292 is defined as the Cylinder 11 Injector Circuit High in the Open Source repository's injector description . This is the specific code characterization used for this diagnostic guide.

• In practice, injector-circuit high codes like P0292 frequently relate to wiring/connectors or injector-driver issues, with injector failure and PCM driver faults as secondary possibilities. The exact distribution will vary by vehicle make/model, maintenance history, and environmental factors.

Practical Tips

• Do not assume the injector is the problem solely based on code; always verify signal integrity and wiring first, because wiring faults commonly produce a P0292-type symptom.
• When performing swaps or wiring tests, label and photograph connectors to ensure you revert to the correct configuration and avoid mis-wiring.
• If replacing the injector, use OEM-recommended parts and re-check the injector seal and seal surfaces to prevent leaks.
• After any repair, perform a thorough road test and monitor live data to confirm the issue is resolved and that no new codes appear.

References (for further reading)

• Source: Wikipedia: OBD-II - Diagnostic Trouble Codes

• Source: Wikipedia: OBD-II - Powertrain Codes

• Open Source: Circuito de controle do injetor - cilindro 11 - sinal alto - explicit description for P0292 in the described repository (injector-circuit-high for cylinder 11).

  • Source: Open Source - Injector circuit description for cylinder 11

This diagnostic guide was generated using verified reference data:

• Wikipedia Technical Articles: OBD-II
• Open-Source OBD2 Data: N/A (MIT)

Content synthesized from these sources to provide accurate, real-world diagnostic guidance.

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