P0304 Code: Ford Escape (2020-2024) - Causes, Symptoms & Fixes

No recalls found in NHTSA database.

Note about the data: The REAL NHTSA data you provided for Ford Escape (2020-2024) does not include any P0304 (cylinder 4 misfire) complaints. The guidance below combines the general meaning of P0304 with common Ford Escape failure modes and practical diagnostic steps. It is not a claim about observed NHTSA complaint trends for P0304 in this model year range, but a thorough diagnostic guide you can use if you see P0304 on a 2020–2024 Escape.

Code meaning and severity

• What P0304 means: Cylinder 4 misfire detected by the Powertrain Control Module (PCM). The engine is not combusting properly in cylinder 4.
• Severity and risk: Misfires can cause rough idle, loss of power, poor drivability, and higher emissions. If the misfire persists, unburned fuel can overheat the catalytic converter and potentially cause damage. Repeated misfires can also lead to catalytic converter failure and reduced fuel economy.
• When you’ll see it: The MIL (Check Engine Light) may illuminate, and a scan tool will read P0304 along with data such as RPM, misfire history, and related system codes.

Common causes on Ford Escape (2020–2024)

• Ignition subsystem
  • Faulty spark plug on cylinder 4 (worn, fouled, or incorrect gap)
  • Faulty ignition coil or coil-on-plug for cylinder 4
  • Worn high-tension ignition coil wiring or connector
• Fuel subsystem
  • Faulty fuel injector on cylinder 4 (stuck open/closed, poor spray pattern)
• Air and intake subsystem
  • Vacuum leak near cylinder 4 (leaking intake manifold boot, vacuum hose, or PCV plumbing)
  • Mass air flow sensor or intake air leaks altering air/fuel mixture
• Fuel delivery and pressure
  • Low fuel pressure affecting cylinder 4 delivery (pump, regulator, or clogged filter)
• Mechanical (less common but critical to check)
  • Low compression in cylinder 4 due to worn piston rings, burnt valve, or valve seating issue
  • Timing chain/buelt or camshaft issues (rare; would affect multiple cylinders)
• Electrical and control
  • Damaged PCM wiring/ground referencing misfire information
  • Related cylinder misfire may be amplified by faulty accessory sensors or harness issues
• Note: The Ford Escape uses coil-on-plug ignition for many engines in this range; cylinder-accessability for 4-cylinder variants varies by engine (e.g., 2.0L EcoBoost I4 vs. 2.5L hybrid), so some steps may require more disassembly than others.

Symptoms you might notice with P0304

• Rough or unstable idle; engine shake at idle
• Hesitation, stalling, or reduced power during acceleration
• Decreased fuel economy or a noticeable drop in engine smoothness
• Check Engine Light (MIL) on or flashing during misfire onset
• Possible intermittent rough running that worsens under load or during cold start
• Noises such as ticking can appear if a misfire is severe (not always)

Diagnostic steps (systematic approach)

Important: Work safely, allow the engine to cool when necessary, and use a proper OBD-II scanner.

• Step A: Confirm and data-verify

  • Read the diagnostic trouble code with a scanner: confirm P0304 and note any freeze-frame data (RPM, load, throttle position at the time of misfire).
  • Check for related codes: P0300 (random/multiple misfire), P0301–P0303, P0305–P0306 (other cylinder misfires), or codes for ignition/fuel systems (P0351–P0354 for coil packs, P0300 family, P0171/P0174, etc.).

• Step B: Inspect ignition for cylinder 4

  • Remove access to cylinder 4 spark plug and inspect its condition: fouled, oil-fouled, worn vs. normal.
  • Check the spark plug gap and replace if worn or fouled. Use the correct heat range and torque as per Ford guidelines (typically a specific torque spec; over- or under-torque can cause misfires).
  • Inspect the ignition coil for cylinder 4: look for cracks, corrosion, heat damage, or a loose boot. Swap test (see Step D).

• Step C: Inspect ignition coil and wiring

  • Resistance test for ignition coil primary/secondary windings (per Ford service specs) and compare to OEM spec.
  • Inspect coil wiring harness and connector for damage, corrosion, or poor connector fit. Clean/repair as needed.

• Step D: Perform a swap test to isolate coil or plug

  • Swap the coil from cylinder 4 to another cylinder (e.g., cylinder 1) and clear the codes. If P0304 moves to the new cylinder, the coil is likely faulty. If the misfire stays on cylinder 4 after swapping, the coil is probably not the root cause; move to Step E.
  • Do the same with the spark plug if you suspect fouling; replacing the plug on cylinder 4 and rechecking is sensible.

• Step E: Inspect and test the fuel injector for cylinder 4

  • Listen for injector operation with a noid light or by observing injector pulse on a scan tool.
  • Swap test: Swap the injector between cylinder 4 and another cylinder to see if the misfire follows the injector.
  • Check injector resistance and spray pattern (fuel rail pressure should be within spec; a fuel pressure test may be warranted if available data suggests low pressure).

• Step F: Check fuel delivery and pressure

  • Measure fuel pressure with a proper gauge to ensure the fuel system is delivering adequate pressure for the engine.
  • Check for symptoms of a weak fuel pump, clogged filter, or faulty regulator.

• Step G: Check for vacuum leaks and air intake issues near cylinder 4

  • Perform a vacuum test or a smoke test to identify leaks around the intake manifold, gaskets, or PCV system in the vicinity of cylinder 4.
  • Inspect hoses and seals for cracks or disconnections.

• Step H: Check cylinder compression and mechanical condition

  • Perform a compression test for cylinder 4 and compare with adjacent cylinders to assess ring/seal condition, valve seating, and timing.
  • If compression is low, further investigation is warranted (valve train, piston rings, head gasket).

• Step I: Review ancillary systems if basic checks fail

  • MAF sensor, idle control, EGR valve, and PCV system can influence mixture and misfire conditions; verify operation and clean if appropriate (and replace if faulty).

• Step J: If no obvious cause identified

  • Clear codes and perform a road test under varying loads to observe misfire conditions.
  • Consider professional diagnosis with more advanced equipment (e.g., lab scope for ignition waveforms, injector pulse width, fuel trim data, ignition coil secondary resistance under load).

Related codes you may see with P0304

• P0300: Random/Multiple misfires
• P0301, P0302, P0303, P0305, P0306: Cylinder 1, 2, 3, 5, 6 misfires respectively
• P0351–P0354: Ignition coil primary/secondary circuit problems for cylinders 1–4
• Other related codes: P0171/P0174 (system too lean or rich), P0130–P0134 (O2 sensor issues) or P030x codes caused by fuel or air system faults
• Note: If multiple cylinders show misfires, the root cause may be fuel delivery, vacuum leaks, or a PCM/communication issue rather than a single spark plug or coil.

Repair options and costs (2025 prices)

Prices can vary by region, labor rate, and exact engine variant (2.0L EcoBoost I4 vs. 2.5L hybrid). All prices shown are rough ranges in USD for typical U.S. shops.

• Spark plug replacement (cylinder 4)

  • Parts: $5–$15 per plug (OEM/Motorcraft or equivalent)
  • Labor: 0.5–1.0 hour
  • Estimated total: $100–$180

• Ignition coil replacement (cylinder 4)

  • Parts: $40–$120
  • Labor: 0.5–1.0 hour
  • Estimated total: $120–$240

• Spark plug + coil replacement (if both are faulty)

  • Parts: $45–$135
  • Labor: 1.0–1.5 hours
  • Estimated total: $200–$350

• Fuel injector service or replacement (cylinder 4)

  • Cleaning (nozzle/pattern cleaning, injector cleaner): $50–$150
  • Replacement injector: $150–$350 parts
  • Labor: 1.0–2.0 hours
  • Estimated total: $200–$600

• Fuel system pressure issue (pump or regulator)

  • Pressure test or repair: $150–$400 (diagnostic + repair as needed)
  • If fuel pump replacement is required: $500–$1,000+ (parts and labor)

• Vacuum leak repair (PCV, hoses, gaskets)

  • Parts: $20–$100
  • Labor: 0.5–1.5 hours
  • Estimated total: $100–$300

• Compression/valve job (mechanical issue)

  • Parts: varies widely; head work or engine repair
  • Labor: highly variable; often 4–12+ hours
  • Estimated total: $1,000–$4,000+ depending on scope

• PCM/ECU replacement (rare)

  • Parts: $200–$600 (plus programming)
  • Labor: 1–3 hours
  • Estimated total: $400–$1,200

Notes:

• If the misfire is caused by a mechanical issue (low compression, valve, timing gear), the repair cost can be substantial.
• Always confirm the root cause before replacing multiple components to avoid unnecessary expenses.
• These are typical ranges; actual prices depend on your local shop, labor rate, and whether OEM parts are used.

DIY vs professional

• DIY-friendly scenarios (lower risk, quick wins):
  • Replacing a single faulty spark plug on cylinder 4
  • Replacing a faulty ignition coil on cylinder 4 (with access)
  • Inspecting/replacing hoses, PCV valve, or simple vacuum leaks
  • Running basic injector tests if you have an appropriate noid light and access to data
• When to involve a professional:
  • If you’ve swapped a coil and/or plug and P0304 persists
  • If you suspect a faulty fuel injector, fuel pressure issue, or compressor/valve problem
  • If you don’t have the tools to perform compression tests, fuel pressure tests, or data-stream analysis
  • If the engine uses a difficult-to-access coil-on-plug arrangement or you’re uncertain about torque specs
• Tools and tips for DIY:
  • Use OEM or equivalent replacement parts
  • Follow Ford’s recommended torque specs for spark plugs and coils
  • Clear codes after service and perform a test drive to verify the fix
  • Document symptoms and any changes in data with a scanner

Prevention

• Regular maintenance per Ford’s schedule
  • Replace spark plugs at the manufacturer-recommended intervals for your engine (often around 60k–100k miles for modern engines; check your owner's manual)
  • Replace ignition coils if symptoms of coil failure appear (misfire, rough idle, or hard starting)
  • Keep the air filter clean and replace as recommended
  • Maintain fuel system health with high-quality fuel and occasional fuel-system cleaner if advised by Ford or your mechanic
  • Inspect and replace vacuum hoses, PCV components, and intake gaskets as part of routine service
  • Use manufacturer-recommended fluids and avoid contamination that can affect sensors
• Prevent aggressive driving patterns that aggravate misfires (e.g., sustained high-load driving without cooling and maintenance)
• If you notice repeated misfires or rough running, address promptly to minimize catalyst and exhaust system damage

Important data note

• The provided data for Ford Escape (2020–2024) shows no P0304 complaints in the supplied set, and no recalls were found in the NHTSA database for this dataset. The diagnostic guide above uses general automotive knowledge and Ford-friendly diagnostic approaches to help you diagnose P0304 on a 2020–2024 Escape.
• If you want more model-specific details (engine variant, exact spark plug part number, or coil part numbers for your exact trim), consult your owner's manual or a Ford service bulletin database, or ask your dealer/mechanic with your VIN and engine code.

If you’d like, tell me your Escape’s engine variant (e.g., 2.0L EcoBoost, 2.5L hybrid, or 1.5L EcoBoost) and your current symptoms, and I can tailor the diagnostic steps and estimated costs more precisely.