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Home / DTC / P0307 — Cylinder 7 Misfire Detected

P0307 — Cylinder 7 Misfire Detected

Detailed page for trouble code P0307.

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Code

P0307

Generic P — Powertrain

Cylinder 7 Misfire Detected

Brand: Generic
Type: P — Powertrain
Views: UK: 20 EN: 23 RU: 22
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty or fouled spark plug in cylinder 7
  • Failed or weak ignition coil (coil-on-plug) for cylinder 7
  • Clogged or failed fuel injector on cylinder 7
  • Low cylinder compression (worn piston rings, burned valve, head gasket)
  • Intake manifold vacuum leak or intake gasket leak near cylinder 7
  • Low fuel pressure or weak fuel pump

Symptoms

  • Check engine light (MIL) illuminated
  • Rough idle or vibration at idle
  • Loss of power and hesitation under load
  • Reduced fuel economy
  • Increased exhaust emissions and possible rotten-egg smell if catalytic affected
  • Occasional hard starting or stalling

What to check

  • Read and record all stored/PENDING codes and freeze-frame data with a scan tool
  • Check misfire counts and identify whether misfire is isolated to cylinder 7 or intermittent
  • Visual inspection: wiring, connectors, coil-on-plug boots, and spark plug for cylinder 7
  • Swap ignition coil from cylinder 7 with a known-good cylinder to see if misfire follows the coil
  • Swap fuel injector (or swap injector harness/connector) with another cylinder to see if misfire follows the injector
  • Check fuel rail pressure with a gauge to confirm system pressure within spec

Signal parameters

  • Misfire count for cylinder 7 (events/cycle or per minute)
  • Short-term fuel trim (STFT) and long-term fuel trim (LTFT) (%)—look for large corrections on the affected bank
  • Injector pulse width (ms) for cylinder 7
  • Ignition coil primary resistance (ohms) and secondary resistance (kΩ) or coil dwell time (ms)
  • Fuel rail pressure (psi / bar) at idle and under load
  • Crankshaft/Camshaft position sensor signals and cam/crank correlation (timing)

Diagnostic algorithm

  1. Read and record all DTCs and freeze-frame data; note operating conditions when P0307 set.
  2. Confirm misfire is current: monitor live misfire counters and identify if it's steady, intermittent, or load-dependent.
  3. Perform visual inspection of spark plug, coil, boot and wiring for cylinder 7; replace or re-seat if damaged.
  4. Swap the ignition coil from cylinder 7 with a known-good cylinder. If misfire moves, replace the coil.
  5. If coil swap is negative, swap the injector (or its connector) with another cylinder. If misfire follows, replace the injector.
  6. Check fuel rail pressure and ensure regulator and pump are within spec; inspect fuel filter if applicable.

Likely causes

  • Worn, fouled or incorrectly gapped spark plug in cylinder 7
  • Failed ignition coil for cylinder 7 (common on coil-on-plug systems)
  • Stuck/failed fuel injector or poor injector spray pattern for cylinder 7
  • Low compression on cylinder 7 (mechanical issue)
  • Damaged wiring or loose connector to coil/injector on cylinder 7

Fault status

⚠️ Status
Engine control detected a misfire specific to cylinder 7. MIL set; increased emissions risk and potential catalytic converter damage if unresolved. Further testing required to identify cause (ignition, fuel, mechanical, or wiring).
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0 - 3.0 hours
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Code

P0307

GWM P — Powertrain

- Ignition order of cylinder 7 disrupted

Brand: GWM
Type: P — Powertrain
Views: UK: 5 EN: 6 RU: 8
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty or fouled spark plug in cylinder 7
  • Failed or weak ignition coil (coil-on-plug) for cylinder 7
  • Clogged or failed fuel injector on cylinder 7
  • Low cylinder compression (worn piston rings, burned valve, head gasket)
  • Intake manifold vacuum leak or intake gasket leak near cylinder 7
  • Low fuel pressure or weak fuel pump

Symptoms

  • Check engine light (MIL) illuminated
  • Rough idle or vibration at idle
  • Loss of power and hesitation under load
  • Reduced fuel economy
  • Increased exhaust emissions and possible rotten-egg smell if catalytic affected
  • Occasional hard starting or stalling

What to check

  • Read and record all stored/PENDING codes and freeze-frame data with a scan tool
  • Check misfire counts and identify whether misfire is isolated to cylinder 7 or intermittent
  • Visual inspection: wiring, connectors, coil-on-plug boots, and spark plug for cylinder 7
  • Swap ignition coil from cylinder 7 with a known-good cylinder to see if misfire follows the coil
  • Swap fuel injector (or swap injector harness/connector) with another cylinder to see if misfire follows the injector
  • Check fuel rail pressure with a gauge to confirm system pressure within spec

Signal parameters

  • Misfire count for cylinder 7 (events/cycle or per minute)
  • Short-term fuel trim (STFT) and long-term fuel trim (LTFT) (%)—look for large corrections on the affected bank
  • Injector pulse width (ms) for cylinder 7
  • Ignition coil primary resistance (ohms) and secondary resistance (kΩ) or coil dwell time (ms)
  • Fuel rail pressure (psi / bar) at idle and under load
  • Crankshaft/Camshaft position sensor signals and cam/crank correlation (timing)

Diagnostic algorithm

  1. Read and record all DTCs and freeze-frame data; note operating conditions when P0307 set.
  2. Confirm misfire is current: monitor live misfire counters and identify if it's steady, intermittent, or load-dependent.
  3. Perform visual inspection of spark plug, coil, boot and wiring for cylinder 7; replace or re-seat if damaged.
  4. Swap the ignition coil from cylinder 7 with a known-good cylinder. If misfire moves, replace the coil.
  5. If coil swap is negative, swap the injector (or its connector) with another cylinder. If misfire follows, replace the injector.
  6. Check fuel rail pressure and ensure regulator and pump are within spec; inspect fuel filter if applicable.

Likely causes

  • Worn, fouled or incorrectly gapped spark plug in cylinder 7
  • Failed ignition coil for cylinder 7 (common on coil-on-plug systems)
  • Stuck/failed fuel injector or poor injector spray pattern for cylinder 7
  • Low compression on cylinder 7 (mechanical issue)
  • Damaged wiring or loose connector to coil/injector on cylinder 7

Fault status

⚠️ Status
Engine control detected a misfire specific to cylinder 7. MIL set; increased emissions risk and potential catalytic converter damage if unresolved. Further testing required to identify cause (ignition, fuel, mechanical, or wiring).
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0 - 3.0 hours
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
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Code

P0307

HUMMER P — Powertrain

Cylinder 7 Misfire Detected

Brand: HUMMER
Type: P — Powertrain
Views: UK: 10 EN: 12 RU: 13
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty or fouled spark plug in cylinder 7
  • Failed or weak ignition coil (coil-on-plug) for cylinder 7
  • Clogged or failed fuel injector on cylinder 7
  • Low cylinder compression (worn piston rings, burned valve, head gasket)
  • Intake manifold vacuum leak or intake gasket leak near cylinder 7
  • Low fuel pressure or weak fuel pump

Symptoms

  • Check engine light (MIL) illuminated
  • Rough idle or vibration at idle
  • Loss of power and hesitation under load
  • Reduced fuel economy
  • Increased exhaust emissions and possible rotten-egg smell if catalytic affected
  • Occasional hard starting or stalling

What to check

  • Read and record all stored/PENDING codes and freeze-frame data with a scan tool
  • Check misfire counts and identify whether misfire is isolated to cylinder 7 or intermittent
  • Visual inspection: wiring, connectors, coil-on-plug boots, and spark plug for cylinder 7
  • Swap ignition coil from cylinder 7 with a known-good cylinder to see if misfire follows the coil
  • Swap fuel injector (or swap injector harness/connector) with another cylinder to see if misfire follows the injector
  • Check fuel rail pressure with a gauge to confirm system pressure within spec

Signal parameters

  • Misfire count for cylinder 7 (events/cycle or per minute)
  • Short-term fuel trim (STFT) and long-term fuel trim (LTFT) (%)—look for large corrections on the affected bank
  • Injector pulse width (ms) for cylinder 7
  • Ignition coil primary resistance (ohms) and secondary resistance (kΩ) or coil dwell time (ms)
  • Fuel rail pressure (psi / bar) at idle and under load
  • Crankshaft/Camshaft position sensor signals and cam/crank correlation (timing)

Diagnostic algorithm

  1. Read and record all DTCs and freeze-frame data; note operating conditions when P0307 set.
  2. Confirm misfire is current: monitor live misfire counters and identify if it's steady, intermittent, or load-dependent.
  3. Perform visual inspection of spark plug, coil, boot and wiring for cylinder 7; replace or re-seat if damaged.
  4. Swap the ignition coil from cylinder 7 with a known-good cylinder. If misfire moves, replace the coil.
  5. If coil swap is negative, swap the injector (or its connector) with another cylinder. If misfire follows, replace the injector.
  6. Check fuel rail pressure and ensure regulator and pump are within spec; inspect fuel filter if applicable.

Likely causes

  • Worn, fouled or incorrectly gapped spark plug in cylinder 7
  • Failed ignition coil for cylinder 7 (common on coil-on-plug systems)
  • Stuck/failed fuel injector or poor injector spray pattern for cylinder 7
  • Low compression on cylinder 7 (mechanical issue)
  • Damaged wiring or loose connector to coil/injector on cylinder 7

Fault status

⚠️ Status
Engine control detected a misfire specific to cylinder 7. MIL set; increased emissions risk and potential catalytic converter damage if unresolved. Further testing required to identify cause (ignition, fuel, mechanical, or wiring).
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0 - 3.0 hours
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P0307

MITSUBISHI P — Powertrain

No.7 cylinder misfire detected

Brand: MITSUBISHI
Type: P — Powertrain
Views: UK: 11 EN: 14 RU: 12
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty or fouled spark plug in cylinder 7
  • Failed or weak ignition coil (coil-on-plug) for cylinder 7
  • Clogged or failed fuel injector on cylinder 7
  • Low cylinder compression (worn piston rings, burned valve, head gasket)
  • Intake manifold vacuum leak or intake gasket leak near cylinder 7
  • Low fuel pressure or weak fuel pump

Symptoms

  • Check engine light (MIL) illuminated
  • Rough idle or vibration at idle
  • Loss of power and hesitation under load
  • Reduced fuel economy
  • Increased exhaust emissions and possible rotten-egg smell if catalytic affected
  • Occasional hard starting or stalling

What to check

  • Read and record all stored/PENDING codes and freeze-frame data with a scan tool
  • Check misfire counts and identify whether misfire is isolated to cylinder 7 or intermittent
  • Visual inspection: wiring, connectors, coil-on-plug boots, and spark plug for cylinder 7
  • Swap ignition coil from cylinder 7 with a known-good cylinder to see if misfire follows the coil
  • Swap fuel injector (or swap injector harness/connector) with another cylinder to see if misfire follows the injector
  • Check fuel rail pressure with a gauge to confirm system pressure within spec

Signal parameters

  • Misfire count for cylinder 7 (events/cycle or per minute)
  • Short-term fuel trim (STFT) and long-term fuel trim (LTFT) (%)—look for large corrections on the affected bank
  • Injector pulse width (ms) for cylinder 7
  • Ignition coil primary resistance (ohms) and secondary resistance (kΩ) or coil dwell time (ms)
  • Fuel rail pressure (psi / bar) at idle and under load
  • Crankshaft/Camshaft position sensor signals and cam/crank correlation (timing)

Diagnostic algorithm

  1. Read and record all DTCs and freeze-frame data; note operating conditions when P0307 set.
  2. Confirm misfire is current: monitor live misfire counters and identify if it's steady, intermittent, or load-dependent.
  3. Perform visual inspection of spark plug, coil, boot and wiring for cylinder 7; replace or re-seat if damaged.
  4. Swap the ignition coil from cylinder 7 with a known-good cylinder. If misfire moves, replace the coil.
  5. If coil swap is negative, swap the injector (or its connector) with another cylinder. If misfire follows, replace the injector.
  6. Check fuel rail pressure and ensure regulator and pump are within spec; inspect fuel filter if applicable.

Likely causes

  • Worn, fouled or incorrectly gapped spark plug in cylinder 7
  • Failed ignition coil for cylinder 7 (common on coil-on-plug systems)
  • Stuck/failed fuel injector or poor injector spray pattern for cylinder 7
  • Low compression on cylinder 7 (mechanical issue)
  • Damaged wiring or loose connector to coil/injector on cylinder 7

Fault status

⚠️ Status
Engine control detected a misfire specific to cylinder 7. MIL set; increased emissions risk and potential catalytic converter damage if unresolved. Further testing required to identify cause (ignition, fuel, mechanical, or wiring).
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0 - 3.0 hours
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

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