Fault code P1301 – a step-by-step guide to diagnosing and fixing it

Error code P1301 is displayed and the check engine light is on - what does this mean?

The DTC P1301 is a manufacturer-specific trouble code that is recognized by the OBD-II/EOBD diagnostics and indicates a problem with the ignition coil or the ignition system of cylinder 1. This fault code mainly occurs in Ford vehicles and indicates misfiring or performance problems in the first cylinder.

What can cause this fault code?

• Defective ignition coil on cylinder 1
• Damaged or worn spark plug
• Broken or corroded cable connections to the ignition coil
• Defective spark plug cable or ignition distributor
• Faulty wiring in the ignition circuit
• Defective engine control unit (ECU)
• Mechanical engine problems such as low compression
• Clogged fuel injectors
• Low fuel pressure

What symptoms occur in parallel with fault code P1301?

• Engine misfiring: Irregular engine running, especially at idling speed
• Loss of power: Noticeable reduction in engine power
• Jerking when accelerating: Engine runs unevenly under load
• Increased fuel consumption: Poorer fuel efficiency
• Exhaust odor: Unburned fuel in the exhaust gas
• Starting problems: Difficulty starting the engine
• Check engine light: Permanent display of the check engine light

How to fix the problem of error code P1301?

• Repairing fault code P1301 requires a systematic diagnosis to identify the exact cause.
• Replace ignition coil of cylinder 1 and check electrical connections
• Replace spark plug and set correct electrode gap
• Replace spark plug cable or ignition distributor cap on older vehicles
• Check wiring to ignition circuit for damage and repair
• Clean or replace fuel injector if clogged
• Diagnose engine control unit and reprogram if necessary
• Carry out compression test and rectify mechanical defects
• Test fuel pressure regulator and fuel pump for proper function