Parts for your 2013 Ford Fiesta-Ignition coils

2013 Ford Fiesta ignition coils: what they do and when to replace them

Ignition coils are relevant on most 2013 Ford Fiesta petrol models. Ford’s own workshop manual and Motorcraft service literature describe coil-on-plug (COP) ignition on the 1.0 EcoBoost and Sigma petrol engines, with a dedicated coil sitting on top of each spark plug. Technical guides from Autodata and Haynes echo this setup. The only exception is the TDCi diesel variants, which use compression ignition and glow plugs—no ignition coils required.

On petrol Fiestas, each ignition coil transforms the 12‑volt supply into the high voltage needed to jump the spark plug gap under load. That crisp, well-timed spark is what keeps the little Fiesta perky around town and smooth on the motorway. Over time, heat, vibration and moisture can fatigue a coil’s windings and boots, leading to misfires—especially noticeable on cold starts or under hard acceleration. Ford’s diagnostic routine (as outlined in their service manual) calls for checking for misfire fault codes (P0300–P0304), inspecting the coil boots for carbon tracking, and verifying power/ground and trigger signals before condemning a coil.

While coils aren’t a fixed-interval service item, they benefit from smart maintenance. Replacing spark plugs at the interval in the Fiesta’s maintenance guide helps reduce coil stress, worn plugs make coils work harder. During servicing, a technician should:

• Visually inspect COP units for cracks, swelling or oil contamination under the bonnet.
• Check for water ingress in the plug wells after washing or heavy rain.
• Use dielectric grease on the boots where specified in Ford/Autodata procedures.
• Scan for misfire codes and address any rough idle or hesitation promptly.

If a coil fails, many workshops replace just the faulty unit after confirming the cause, then road-test and recheck. When multiple coils show age-related damage, replacing the set can save repeat visits. Sticking with quality Motorcraft-spec or reputable aftermarket coils avoids drivability niggles. It’s also worth checking the Fiesta’s crankcase ventilation and any rocker cover leaks—oil in the plug tubes can shorten coil life.

Diesel Fiesta owners can skip all this, their cars ignite fuel by compression and use glow plugs for cold starts. That’s why there’s no ignition coil on TDCi models—a point backed by Ford’s diesel system documentation and common-rail diesel training material.

• Does a 2013 Ford Fiesta have ignition coils?
  Most petrol models do, using a coil-on-plug setup—one coil per cylinder. The TDCi diesel versions don’t use ignition coils because they run compression ignition and rely on glow plugs for cold starts.
• How often should Fiesta ignition coils be replaced?
  There’s no set kilometre interval in Ford’s schedules. Coils are replaced when tests confirm a fault. Regular plug changes, keeping moisture out of the plug wells, and addressing oil leaks help coils last longer.
• Can driving with a misfiring coil damage other components?
  Yes. Persistent misfires can overheat and damage the catalytic converter and strain the ignition and fuel systems. It’s best to diagnose and repair promptly if the check engine light flashes or the engine runs rough.