P0302 Code: Dodge Durango (2021-2024) - Causes, Symptoms & Fixes

Below is a comprehensive diagnostic guide for OBD2 code P0302 (Cylinder 2 misfire) as it relates to 2021–2024 Dodge Durango. Data from the provided NHTSA extract shows no owner complaints and no recalls for this exact make/model/year/issue combination. No recalls found in NHTSA database. Data limitations: there are no complaint counts or recall notices to rely on for model-specific misfire trends, so this guide combines general OBD2 misfire diagnostics with Durango-specific ignition/fuel-system knowledge.

CODE MEANING AND SEVERITY

• What P0302 means: P0302 is a misfire fault code indicating that the engine’s PCM detected a misfire in cylinder 2. Misfire means the cylinder did not fire properly, resulting in incomplete combustion.
• Severity and symptoms you might notice:
  • Rough idle or engine shake
  • Power loss or hesitation under acceleration
  • Reduced fuel economy
  • Engine may run noisily or feel “jerky”
  • MIL (Check Engine Light) illuminated
  • In persistent misfires, risk of catalytic converter overheating/damage due to unburned fuel entering the exhaust
• Data note: No NHTSA complaints were listed for this issue on this model/year, and there are no recalls in the provided data. This means no model-specific complaint trends or recalls are available from the dataset. Always treat misfire as potentially serious and address promptly.

COMMON CAUSES ON DODGE DURANGO

Durangos (2021–2024) use modern ignition/fuel systems with coil-on-plug coils on many engines (3.6L V6, 5.7L Hemi, etc.). Cylinder 2 misfires can originate from several root causes, often related to the coil, plug, or injector for that cylinder, but also possible from mechanical or vacuum issues. Common causes include:

• Ignition system
  • Faulty ignition coil for cylinder 2 (coil pack or coil-on-plug failure)
  • Spark plug worn, fouled, or incorrect gap
  • Damaged spark plug boot or damaged/loose wiring to the coil
• Fuel system
  • Faulty fuel injector for cylinder 2 (sticking, leaking, or improper spray)
  • Low fuel pressure or fuel delivery issue affecting cylinder 2
• Air and vacuum/engine breathing
  • Vacuum leak near cylinder 2 (gasket, intake manifold gasket, hoses)
  • Mass air flow (MAF) sensor or air intake leak causing fuel trim abnormalities
• Mechanical (less common but possible)
  • Low compression in cylinder 2 due to valve, piston, or ring issues
  • Timing concerns or cam/crank sensor issues that intermittently affect a single cylinder (less common)
• Electrical/PCM
  • Wiring harness or connector issues to cylinder 2 coil or injector
  • Faulty PCM/ECU processing (rare but possible)

SYMPTOMS

• The MIL is on with code P0302
• Rough idle or rough running at idle
• Reduced acceleration and power, more noticeable under load
• Poor fuel economy
• Occasional stalling or hesitation, especially in stop-and-go driving
• Localized misfire symptoms (you might notice the engine running smoother when cylinder 2 is intentionally swapped testing, see Diagnostic Steps)
• In some cases, no obvious symptoms beyond the MIL early on

DIAGNOSTIC STEPS

Note: This is a practical, systematic approach. If you’re not comfortable performing some steps, seek a professional.

• A. Verify and document

  • Retrieve the freeze-frame data and any pending DTCs. Confirm P0302 is current and note ignition-related data (RPM, load, fuel trim, ignition timing if accessible).
  • Check for additional misfire codes (P0301, P0303, etc.) or related codes (P0352 for coil 2, P035x for coil circuits, P0300 for random/multiple misfires).

• B. Visual inspection

  • Inspect spark plug in cylinder 2: fouling, gap, damage, oil deposition, thread condition.
  • Inspect ignition coil/cylinder 2 coil boot and wiring for cracks, corrosion, or poor connection.
  • Check for cracked or damaged injector wiring or connectors.
  • Look for vacuum leaks around intake manifold, gaskets, hoses near cylinder 2.

• C. Basic ignition and fuel checks

  • Spark plug service: replace cylinder 2 plug if worn or fouled; consider replacing all 6 plugs if the plugs are due or if you find signs of wear.
  • Coil test: swap cylinder 2 coil with another cylinder’s coil (e.g., cylinder 4) and clear codes to see if the misfire moves to the new cylinder. If P0304 appears after swap, the coil is likely faulty; if P0302 remains, the problem may be elsewhere (plug, injector, or mechanical).
  • Injector check: measure injector resistance for cylinder 2 and compare to factory spec; listen for injector operation with a mechanic’s stethoscope or use a noid light to verify injector pulse with the engine cranking.
  • Fuel system: verify fuel pressure is within spec for the Durango engine in question (sport/trim variations). Low pressure can cause misfires under load.

• D. Cylinder-specific tests

  • Compression test: test all cylinders, paying attention to cylinder 2. Low compression indicates mechanical issues (valve, piston, rings, head gasket) that require further diagnosis (e.g., leak-down test).
  • Leak-down test: if compression is low, perform a leak-down test to determine whether the issue is intake/exhaust valve, ring sealing, or gasket-related.

• E. Air and exhaust checks

  • Inspect and test for intake leaks (throttle body gasket, vacuum hoses). A leak near the intake can produce misfires.
  • Check for exhaust restrictions or downstream O2 sensor issues that could cause abnormal fueling and misfire patterns.

• F. Reproduce and verify

  • After repairing or replacing suspected components (plug, coil, injector, vacuum seal, etc.), clear codes and run the vehicle through drive cycles to confirm the misfire is resolved and cylinder 2 no longer shows a fault.

• G. When to seek professional help

  • If the misfire persists after substituting known-good coils and plugs, or if compression is low, or if you are not equipped to perform high-precision fuel/air/fuel-pressure testing, a professional with a scope and fuel-rate testing equipment is recommended.

RELATED CODES

• P0300: Random/Multiple misfires detected
• P0301, P0303, P0304, P0305, P0306, P0307, P0308: Cylinder 1–8 misfires (P0302 specifically for cylinder 2)
• P0350–P0358: Ignition coil primary/secondary circuit faults (P0352 would indicate coil 2 circuit issue; relevant if coil 2 is suspected)
• Other fuel and air codes may surface if the misfire is influenced by fuel trim (e.g., P0171/P0174), or sensors (MAF, MAP, O2 sensor) reacting to the misfire

REPAIR OPTIONS AND COSTS (2025 PRICES)

Note: Prices vary by region and shop. The ranges below reflect typical U.S. market pricing in 2025 and assume standard labor rates of roughly $90–$150 per hour. These estimates cover common Durango engines (e.g., 3.6L V6, 5.7L Hemi) and are for parts + labor.

• Spark plug replacement (all six plugs, common intervention if wear is evident or as preventive measure)

  • Parts: $24–$120 (6 plugs at ~$4–$20 each; OEM or aftermarket)
  • Labor: 0.5–1.5 hours
  • Estimated total: $100–$350

• Ignition coil replacement (one cylinder, cylinder 2)

  • Parts: $50–$150
  • Labor: 0.4–1.0 hour
  • Estimated total: $90–$210
  • Quick diagnostic note: swapping the suspect coil with another cylinder is a common test to determine if the coil is at fault.

• Fuel injector replacement (cylinder 2)

  • Parts: $60–$180
  • Labor: 1–2 hours
  • Estimated total: $140–$420

• Fuel system cleaning or injector service (non- replacement)

  • Parts: $0–$60
  • Labor: 0.5–1.0 hour
  • Estimated total: $60–$180
  • Note: Such cleaning may provide only temporary relief if a mechanical injector fault exists.

• Compression test / mechanical repair (valve, rings, head gasket, etc.)

  • Parts: Varies widely
  • Labor: 2–6+ hours depending on the issue
  • Estimated total: $1,000–$3,500+ (could be higher for extensive engine work)

• PCM/ECU replacement or programming (rare for a single-cylinder misfire)

  • Parts: $300–$900
  • Labor/Programming: $100–$400
  • Estimated total: $400–$1,300

• Wiring harness/connector repair

  • Parts: $20–$150 (depending on connector/repair)
  • Labor: 0.5–2.0 hours
  • Estimated total: $60–$300

• Vacuum leak repair (gasket, hose replacement)

  • Parts: $10–$50
  • Labor: 0.5–1.5 hours
  • Estimated total: $60–$180

No recalls found in NHTSA database for this issue on this model/year in the provided data.

DIY VS PROFESSIONAL

• DIY-friendly work (if you have basic tools and experience):
  • Spark plug inspection/replacement (for cylinder 2 or all six)
  • Swapping ignition coils to test for coil fault
  • Inspecting and replacing simple vacuum hoses or intake components
  • Basic fuel-system checks (resistance tests for injectors, using a noid light, basic fuel pressure test with a gauge)
• Moderate to advanced DIY tasks:
  • Fuel injector replacement (requires accuracy and some comfort with fuel delivery systems)
  • Fuel pressure diagnosis and wiring/connector checks
  • Compression and leak-down testing (requires a compression gauge and some experience)
• Professional level:
  • Persistent misfire after coil/plug/injector service
  • Suspected mechanical issues (low compression, valve problems)
  • ECU/PCM concerns
  • If you do not have the diagnostic tools (OBD-II scan tool with live data, oscilloscope/fuel pressure gauge, noid light, compression gauge) or the experience to interpret data, a professional tech is recommended.

Tips for DIY success:

• Always work on a cool engine and disconnect the battery when removing ignition-related components.
• Use the correct spark plug type, heat range, and torque specification per Dodge service guidance (do not overtighten spark plugs).
• When swapping coils for diagnostic testing, ensure the engine has cooled and use the proper torque and seals on coil boots.
• Clear any DTCs after repairs and perform a proper drive cycle to confirm the fix.

PREVENTION

• Regular maintenance per Durango’s service schedule:
  • Replace spark plugs at the manufacturer-recommended intervals or when worn; on many engines, a full set replacement is wise if one is showing wear or if other plugs are near service life.
  • Use the recommended spark plug type and ignition coils. Avoid counterfeit or low-quality components.
  • Maintain clean air intake and fuel system: replace air filter regularly; consider occasional fuel system cleaner suitable for your engine, and use high-quality gasoline.
  • Keep fuel injectors and fuel system components in good condition; address rough running or suspected injector issues promptly.
  • Monitor ignition system: inspect coil boots, wiring, and connectors for wear or damage.
  • Address vacuum leaks promptly; replace gaskets and hoses as needed.
  • Maintain proper compression by addressing engine wear early; perform periodic compression checks on high-mileage engines.
  • Address misfires promptly: prolonged misfires can stress the catalytic converter and other exhaust components.