2014-2019 Ford Fiesta Ignition Coil Failure: Misfires, Diagnosis, and Replacement

Symptoms of a Failing Ignition Coil Pack

When the ignition coil pack in your 2014-2019 Ford Fiesta begins to fail, the signs are usually hard to miss. Because it's responsible for creating the spark for all four cylinders, a failure can significantly impact engine performance. You'll likely experience one or more of the following symptoms:

• Engine Misfires: This is the most common symptom. You may feel the engine stumble, jerk, or hesitate during acceleration. It can feel like a loss of power or a shudder from the engine bay.
🎬 Watch: Diagnosing a Fiesta misfire and loss of power
• Rough Idle: When the car is stopped, the engine may idle unevenly, causing the whole vehicle to vibrate or shake.
• Check Engine Light: A failing coil will almost always trigger the Check Engine Light. If the light is flashing, it indicates a severe misfire that could be dumping unburned fuel into the exhaust, risking damage to the catalytic converter.
• Reduced Power and Poor Acceleration: Your Fiesta may feel sluggish and slow to respond when you press the gas pedal.
• Decreased Fuel Economy: When the engine isn't burning fuel efficiently due to weak or inconsistent spark, your gas mileage will suffer.
• Stalling: In more severe cases, the engine may stall while idling or even while driving because it isn't getting enough power to keep running.
• Difficulty Starting: A weak or dead coil pack can make it difficult for the engine to turn over and start.

Common trouble codes associated with ignition coil failure include:

• P0300: Random/Multiple Cylinder Misfire Detected
• P0301, P0302, P0303, P0304: Misfire Detected in a specific cylinder (1, 2, 3, or 4).
• P0351, P0352, P0353, P0354: Ignition Coil Primary/Secondary Circuit Malfunction for a specific cylinder.

Known Issues, TSBs, and Recalls

While there are no specific recalls for the ignition coil pack itself on the 2014-2019 Fiesta, Ford did issue a Technical Service Bulletin (TSB) that is relevant. TSB #SSM 45988 mentions that 2015-2016 Fiesta models with the 1.6L engine may show a Check Engine Light with codes P0351 and/or P0352, which can cause rough running. This indicates that Ford is aware of potential circuit malfunctions in the ignition system for these model years. Other major recalls for this Fiesta generation concern door latches, fuel pumps on some 2014-2015 models, and potential engine overheating on ST models, but none directly target the ignition coil on the non-turbo engine.

Buying a Used Ignition Coil: What to Inspect

A high-quality, low-mileage used OEM ignition coil can be a reliable and cost-effective alternative to new parts, especially when compared to cheap aftermarket options. Original Ford (Motorcraft) parts are built to a higher standard than many aftermarket replacements. Here’s what to check before buying a used coil pack:

• Inspect the Housing: Carefully check the black plastic housing for any cracks, hairline fractures, or signs of melting. Heat and vibration are the enemies of ignition coils, and any cracks can allow moisture in, leading to failure.
• Check the Electrical Connector: Look at the 3-pin connector port. The pins should be clean, straight, and free of any green or white corrosion. A corroded connector is a major red flag.
• Examine the Spark Plug Towers: Inspect the four towers where the spark plug wires connect. Look for any white, chalky residue or black carbon tracks. These are signs of arcing, where high-voltage electricity has escaped, indicating the coil is failing.
• Ask for Mileage and Vehicle History: If possible, choose a coil from a lower-mileage vehicle. An ignition coil from a car with 50,000 miles is a much better bet than one from a car with 150,000 miles.
• Why Used OEM is Often Better: The materials and winding techniques used in genuine Motorcraft coils are designed specifically for your Fiesta's engine management system. Many budget aftermarket coils use inferior materials that can't withstand engine bay temperatures, leading to premature failure and leaving you stranded. A used OEM part has already proven its durability.

Replacement Guide (Difficulty: 1/5)

Replacing the ignition coil pack on a 1.6L Fiesta is one of the easiest repairs you can perform. It is highly accessible at the top of the engine and requires only basic hand tools. The entire job can typically be done in less than 30 minutes.

1. Disconnect the Battery: As a safety precaution, disconnect the negative terminal of the battery.
2. Locate the Coil Pack: Open the hood and look at the top of the engine. The ignition coil pack is a rectangular block with four towers that the spark plug wires connect to.
3. Disconnect the Electrical Connector: Press the tab on the 3-pin electrical connector and pull it straight off the coil pack.
4. Remove the Spark Plug Wires: Gently twist and pull each of the four spark plug wires off the towers of the coil pack. It's helpful to label them 1-4 with masking tape so you can reconnect them in the correct order.
5. Unbolt the Coil Pack: The coil pack is held onto the engine with four bolts, typically requiring a T25 Torx driver or a small socket. Remove these bolts.
6. Install the New Coil Pack: Place the new or used coil pack in position and reinstall the four mounting bolts. Tighten them until they are snug, but do not overtighten to avoid cracking the plastic.
7. Reconnect Wires and Connector: Push the spark plug wires firmly back onto their corresponding towers until they click into place. Reconnect the electrical connector.
8. Reconnect the Battery: Reattach the negative battery terminal. Start the engine to confirm the repair.
🎬 See this step-by-step coil pack replacement walkthrough

Cost Comparison

Prices can vary by location and supplier, but this provides a general cost expectation.

Frequently Asked Questions (FAQ)