P0304 Code: 2018 Ford F-150 – What It Means & Cost to Fix

2018 Ford F-150 P0304 Code: Cylinder 4 Misfire Expert Diagnosis

When your 2018 Ford F-150 displays the P0304 code, the engine control module has identified consistent misfires in cylinder 4. The 13th generation F-150 offers multiple proven engine options.

2018 F-150 Engine Options

The 2018 F-150 offers the 3.3L V6, 2.7L EcoBoost V6, 3.5L EcoBoost V6, and 5.0L Coyote V8. At this age, component wear becomes more common. Cylinder 4 location varies by engine configuration.

Common Causes

  • Ignition Coil Degradation: Age-related failures common
  • Spark Plug Wear: May be past service interval
  • Fuel Injector Issues: Direct injection deposits
  • Carbon Buildup: Significant at this age on EcoBoost
  • Vacuum Leaks: Aged gaskets and hoses

Diagnostic Approach

Use Ford diagnostics or FORScan for detailed access. At this age, systematic testing is important. Monitor misfire counts. Test ignition components systematically.

Repair Solutions

Replace aging ignition coils with Motorcraft parts. Install new spark plugs. Carbon cleaning beneficial on EcoBoost models. Repair vacuum leaks.

Parts & Tools for This Case

Based on our investigation, these parts may be needed for this repair.

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