Parts for your 2014 Toyota Vitz|yaris-Ignition coils

2014 Toyota Vitz/Yaris ignition coils — what they do and when to replace them

Ignition coils are absolutely fitted to the 2014 Toyota Vitz/Yaris. Technical references including Toyota’s New Car Features (P13# series), the Toyota Repair Manual for the XP130 platform, and the Toyota Electronic Parts Catalogue all specify a Direct Ignition System (DIS) with individual coil-on-plug units for the 1KR‑FE (1.0‑litre), 1NR‑FE (1.3‑litre), 1NZ‑FE (1.5‑litre) and the hybrid 1NZ‑FXE engines. Denso service data supports this, listing dedicated coil-on-plug assemblies for these engines.

On this model, each cylinder gets its own coil mounted directly on the spark plug. The coil’s job is to step the 12V battery supply up to the high voltage needed to jump the spark plug gap and ignite the air–fuel mix. That sharp, well-timed spark is what keeps the Vitz/Yaris running smoothly, sipping fuel, and meeting emissions targets.

Coils aren’t a scheduled replacement item like spark plugs, but they do age from heat, vibration, and moisture. During routine servicing, it’s smart to have the technician check the coil boots for cracking or carbon tracking, ensure connectors are snug and clean, and confirm there’s no oil or water under the bonnet pooling around the plug tubes. Spark plugs should be replaced at the recommended intervals (typically long-life iridium at around 100,000 km), because worn plugs make coils work harder and can shorten their life.

• Typical symptoms of a failing coil: rough idle, reduced power, higher fuel use, a flashing or steady check engine light, and fault codes like P0300 (random misfire), P0301–P0304 (cylinder-specific misfire), or P0351–P0354 (coil circuit).
• Diagnosis tip: on non-hybrid models, a swap test can isolate a bad coil—move it to another cylinder and see if the misfire code follows. Always follow safe battery and high-voltage handling practices, especially on hybrid variants.
• Replacement advice: use quality coils (genuine or reputable aftermarket), lightly grease the inside of the boot with dielectric compound, seat the coil squarely, and tighten the hold-down fastener to factory spec. It’s fine to replace a single failed coil, though high-kilometre cars may benefit from doing a matched set.

Look after the coils by keeping the engine covers and cowl seals in good nick to prevent water ingress, sticking to the correct plug gap and spec, and scanning for codes early if the car starts to stumble. A healthy set of coils can easily run well past 150,000 km when the basics are right.

How many ignition coils does a 2014 Vitz/Yaris have?

It’s one coil per cylinder. That’s three coils for the 1KR‑FE 1.0‑litre (3‑cylinder), and four coils for the 1NR‑FE or 1NZ‑FE 4‑cylinder engines. The hybrid 1NZ‑FXE also uses four coil-on-plug units.

What are the common signs and fault codes of a bad coil?

Drivers usually notice a rough idle, sluggish acceleration, and a check engine light. The ECU often logs P0300 (random misfire) or P0301–P0304 for the affected cylinder. Coil circuit codes like P0351–P0354 can also appear. Address it early to protect the catalytic converter.

Should all coils be replaced at once?

Not necessarily. If one coil fails on a low-to-mid kilometre car, replacing the single faulty unit is fine. On higher kilometre vehicles, or if multiple coils test weak, doing a matched set can save repeat labour and keep the tune balanced.