P0302 Code: Dodge Charger (2021-2023) - Causes, Symptoms & Fixes

COMPREHENSIVE DIAGNOSTIC GUIDE FOR OBD2 CODE P0302 ON 2021-2023 DODGE CHARGER

Important data note (data limitations)

• Real NHTSA data provided: OWNER COMPLAINTS — No complaints found for this make/model/year/issue; OFFICIAL RECALLS — No recalls found in NHTSA database.
• Therefore, no model-year-specific NHTSA complaints or recalls are cited here. This guide uses general automotive knowledge for the diagnostic process, with emphasis on what you’d typically check for P0302 on a modern Dodge Charger. If you have access to dealership service data or Factory Service Manuals for your exact engine (3.6L V6, 5.7L Hemi, etc.), use those procedures as the primary reference.
• Data limitations: Absence of complaints/recalls in the provided data does not guarantee the issue cannot occur in real life; it simply means there were no listed items in the supplied dataset.

CODE MEANING AND SEVERITY

• Code: P0302
• Meaning: Cylinder 2 misfire detected. The Powertrain Control Module (PCM) detected an abnormal combustion event in cylinder 2 during a misfire test cycle.
• Severity:
  • Drivability: Moderate. You’ll typically notice rough idle, reduced power, and possibly hesitation or stumbling, especially at acceleration.
  • Emissions/fuel economy: Misfires waste fuel and can raise exhaust emissions; prolonged misfires can overheat the catalytic converter and cause damage.
  • Reliability: If left unrepaired, misfires can move to other cylinders or lead to catalytic converter damage.

COMMON CAUSES ON DODGE CHARGER

Many Charger engines share similar misfire causes. For cylinder 2 specifically, consider:

• Ignition system (cylinder 2)

  • Worn or fouled spark plug in cylinder 2
  • Faulty ignition coil for cylinder 2 (coil-on-plug common)
  • Bad ignition coil boot/wiring to cylinder 2
  • Weak battery or charging issues affecting spark quality

• Fuel system (cylinder 2)

  • Failing or sticking fuel injector for cylinder 2
  • Low fuel pressure to the cylinder (fuel pump, fuel filter, regulators)
  • Contaminated fuel or fuel delivery issues

• Air intake and sensors

  • Vacuum leak near cylinder 2 (intake manifold gasket, hoses, PCV)
  • Mass Air Flow (MAF) sensor or related airflow issues affecting fueling
  • Faulty or dirty air intake components around cylinder 2

• Mechanical and internal engine

  • Decreased compression in cylinder 2 (valve, piston ring, bore, head gasket, valve seating)
  • Timing chain/bollow/variable cam timing issues (less common but possible)
  • Internal engine wear or damage localized to cylinder 2

• Miscellaneous

  • Dirty or contaminated spark plug boot/coil connector causing intermittent spark
  • Faulty PCM/PCM misinterpretation (rare)

SYMPTOMS

• Rough or intermittently rough idle, especially at cold start or idle in gear
• Noticeable loss of power or sluggish acceleration
• Hesitation or stumbling during acceleration
• Increased exhaust emissions or odor of unburned fuel
• Check Engine Light (CEL) ON with P0302 stored or pending
• Possible mild vibration or shaking at idle
• In some cases, P0302 may appear with P0300 (random/multiple misfires)

DIAGNOSTIC STEPS

A systematic flow you can follow (adapt to your engine variant; 2021-2023 Chargers use various engines, including 3.6L V6 and Hemi variants)

A. Confirm codes and context

• Use a good OBD-II scanner to confirm P0302 and check for any related codes (P0300, P0301, P0303, etc.).
• Review freeze-frame data (RPM, load, fuel trim, misfire counts) to understand operating conditions when the misfire occurred.

B. Basic inspection and quick tests

• Visual inspection: Inspect spark plug 2 for gap, wear, oil/fouling; inspect the coil boot/connector for corrosion or loose connection.
• Swap test (diagnostic flag test for ignition coil or spark plug):
  • If you have a coil-on-plug setup, you can swap the coil from cylinder 2 with another cylinder (e.g., cylinder 4) and recheck the code after a short drive. If P0302 moves to the other cylinder, the coil could be faulty.
  • If possible, swap spark plugs between cylinder 2 and another cylinder to see if the misfire follows the plug.

C. Ignition system checks

• Spark plug replacement: If the plug is worn, fouled, or damaged, replace with the recommended plug type and gap per the service manual.
• Coil check: For cylinder 2 coil, test for proper primary/secondary resistance (use service specs). Look for signs of overheating or arcing.
• Wires and connectors: Inspect coil-to-plug boot; ensure a solid electrical connection; replace damaged boots or connectors.

D. Fuel system checks

• Fuel injector 2:
  • Listen for injector operation with a mechanic’s stethoscope or ultrasonic/balancer method while engine runs (listen for a ticking sound indicating injection).
  • Injector resistance check (compare to spec for cylinder 2 vs known-good cylinder).
  • Noid light test to verify injector driver signal from PCM.
  • If feasible, perform a balance test by swapping injectors between cylinders (e.g., swap 2 with 4) and observe if the misfire follows the injector.
• Fuel pressure: Check rail pressure with the appropriate gauge to ensure adequate pressure; look for pressure drop under load.
• Fuel contamination: Consider fuel conditioner or replacing a contaminated fuel sample (in extreme cases).

E. Air and vacuum checks

• Vacuum leaks: Inspect hoses and intake manifold gaskets around cylinder 2 for leaks; use a smoke machine if available.
• MAF/air intake: Check MAF sensor readings with a scan tool and clean/inspect the sensor if contaminated.

F. Mechanical checks

• Compression test: Perform a compression test on cylinder 2 (and compare with cylinder 1 and 3 or the rest of the bank). Significantly lower compression indicates a mechanical issue (valve, piston, ring, head gasket).
• If compression is low, further diagnosis may be required (leak-down test, cylinder leak analysis, valve seating).

G. ECU/PCM and software

• If all hardware tests pass and misfire persists, check for available software updates or TSBs for your specific engine and model year. (Note: The provided data does not list recalls/TSBs; consult official Chrysler/ Dodge service portals for updates.)

H. Post-repair verification

• Clear codes and perform a brief test drive to verify that P0302 does not reappear under idle and light-to-moderate load.
• Monitor live data: fuel trims, misfire counters, RPM drop, and injector activity to confirm the fix.

RELATED CODES

• P0300: Random/Multiple Cylinder Misfire Detected (often appears with P0302 when misfires are not isolated)
• P0301, P0303, P0304, P0305, P0306, P0307, P0308: Cylinder-specific misfire codes (depending on engine configuration; 6- or 8-cylinder variants)
• P0171/P0174: System Too Lean (Bank 1 or Bank 2) — sometimes misfires are caused by lean conditions
• P0507: Idle Control System RPM Higher Than Expected (may accompany misfire in some cases)

REPAIR OPTIONS AND COSTS (2025 PRICES)

Note: Actual costs vary by region, labor rates, and engine variant. Prices shown are rough ranges in USD and intended as estimates only. Labor rates often range from roughly $80–$150 per hour depending on location and shop.

A. Spark plug replacement for cylinder 2 (with or without coil replacement)

• Parts:
  • Spark plug (if replacement needed): $5–$15 each (usually one plug for cylinder 2)
  • Spark plug wires/boots (if applicable): $10–$60
  • Ignition coil for cylinder 2 (if needed): $60–$120
• Labor: 0.5–1.5 hours
• Estimated total: $120–$280 (could be higher if multiple parts are replaced or other cylinders are addressed)

B. Ignition coil replacement (cylinder 2 coil on plug)

• Parts: Coil $60–$120
• Labor: 0.5–1.0 hour
• Estimated total: $100–$180

C. Fuel injector issue (injector 2 cleaning or replacement)

• Injector cleaning (or solvent cleaning) if feasible: $0–$100 (often DIY)
• Injector replacement (single injector 2): $150–$450 (parts+labor)
• If multiple injectors affected or advanced repair required: higher
• Labor: 1.0–2.0 hours
• Estimated total: $200–$550

D. Fuel system and fuel pressure repair (pumps, regulators, lines)

• Parts: $50–$350 depending on component
• Labor: 1.0–2.0 hours
• Estimated total: $150–$700

E. Vacuum leak repair (manifold gasket, hoses)

• Parts: $20–$150
• Labor: 1.0–2.0 hours
• Estimated total: $100–$350

F. Mechanical (low compression or valve/seat issues)

• Compression-related repairs can be substantial
• Parts: head gasket, valve work, rings, etc. can range from $500–$4,000+ depending on extent
• Labor: 3.0–12.0 hours (engine disassembly may be required)
• Estimated total: $1,000–$6,000+

G. ECU/PCM software update or repair (rare)

• Software update: typically $0–$150 (some dealers may charge diagnostic or update fee)
• PCM replacement: $800–$1,800 (part + labor)

Key notes on costs:

• If the misfire is isolated to cylinder 2 and is a simple plug/coil issue, the total can be under $200–$300 with DIY or inexpensive professional service.
• If the misfire is due to a failing injector or a vacuum/air-leak, costs can range from roughly $150 to $700.
• If the root cause is mechanical (low compression, valve timing issues), costs can rise substantially.

DIY vs PROFESSIONAL

DIY considerations:

• Suitable for confident DIYers with basic tools: you can replace a spark plug and inspect/swap the ignition coil; test injector operation with scanning tools and a noid light; inspect for vacuum leaks; perform a basic compression check.
• Cautions:
  • Direct-injection engines or modern coil-on-plug setups require careful handling of ignition coils (high voltage) and may require special tools.
  • Fuel system work can be hazardous; avoid fuel exposure and ensure the engine is off and cooled.
  • If you don’t have a compression tester or fuel pressure gauge, you may miss root causes.
• When to DIY: simple plug/coil issues, easy injector swaps, light cleaning, vacuum-leak checks, and basic data-monitoring with an OBD-II scanner.

Professional considerations:

• If the misfire persists after basic ignition checks, or if you have no experience with fuel injectors, compression tests, or fuel pressure testing, a professional diagnosis is recommended.
• A shop will typically perform a cylinder balance test, cylinder compression test, injector amp draw/flow checks, and may perform a leak-down test to pinpoint issues.
• Expect to pay for labor time and diagnostic fees (often around $100–$150 for diagnostic, sometimes waived with repair).

PREVENTION

• Regular maintenance on schedule:
  • Replace spark plugs at the manufacturer-recommended intervals for your engine (timing and type vary by engine; use OEM or equivalent recommended plug type).
  • Replace ignition coils or coil boots as needed if signs of wear or heat exposure appear.
  • Replace fuel filters (if applicable) and use high-quality fuel.
  • Perform periodic cleaning of the intake and throttle body to avoid buildup that can contribute to misfires.
• Air and vacuum integrity:
  • Inspect and replace intake hoses/PCV hoses if cracked or leaking.
  • Check for vacuum leaks around cylinder 2 and throughout the intake manifold.
• Fuel system care:
  • Use clean fuel; consider a fuel system cleaner occasionally if recommended by the vehicle’s manufacturer.
• Fuel economy and engine health:
  • Address misfires promptly to reduce risk of catalytic converter damage and to maintain efficiency.
  • If you notice a pattern of misfires (recurrent P0302), address issues quickly to avoid long-term damage.

Bottom line

• P0302 on a 2021–2023 Dodge Charger indicates a cylinder 2 misfire. The root cause can range from a simple worn spark plug or faulty coil to a clogged injector, vacuum leak, low fuel pressure, or even a mechanical problem. Start with ignition and fuel delivery checks, then move to air leaks, then mechanical tests if needed. Because this code can have multiple valid root causes, a methodical diagnostic approach, starting with the easiest-to-check items, is best.
• No recalls found in NHTSA database for this data set. No complaints found in the data provided. This guide uses general automotive diagnostic practices and the engine-specific considerations typically encountered in Dodge Charger applications.