Parts for your 2004 Ford Territory-Ignition coils

2004 Ford Territory ignition coils — what they do and how to look after them

Ignition coils are absolutely relevant to the 2004 Ford Territory. The first-generation Territory (SX) runs Ford’s 4.0‑litre Barra inline-six petrol engine, which uses six individual coil-on-plug ignition coils—one per cylinder. This setup is documented in the Ford Territory SX Workshop Manual and Ford Australia’s BA/Barra engine technical training materials, and it’s echoed by major parts catalogues from Bosch and NGK listing direct-fit COP coils for 2004 Territory models. So yes, if a 2004 Territory is coughing, missing, or down on power, the ignition coils are firmly on the shortlist.

The job of each coil is to take the battery’s low voltage and step it up to the big spark needed at the plug. On the Barra, the pencil-style coils sit directly over the spark plugs under the rocker cover trim. When they’re healthy, you get smooth idle, clean starts, and crisp throttle response. When they’re tired, you’ll often see rough idle, hesitation under load, poor fuel economy, and the odd flashing MIL with misfire codes (P0300–P0306).

As part of servicing a 2004 Territory, it’s smart to inspect the coils whenever the spark plugs are due (often around the 100,000 km mark, or earlier if there are misfire symptoms). Common Territory/Barra quirks include oil seeping past the rocker cover gasket into the plug tubes, which can soak coils and cause misfires—fix the gasket before throwing new parts at it.

• Look for cracking or carbon tracking on the coil bodies and boots.
• If one coil fails at higher kilometres, consider replacing the full set to save repeat labour.
• Use quality coils and the correct heat‑range plugs, avoid mixing old and new coils if misfires persist.

1. Disconnect the battery and lift the engine cover.
2. Unplug the coil connectors, remove coil retaining bolts, and pull the coils straight up.
3. Blow out plug wells, fit new plugs (to spec), apply a light smear of dielectric grease to the coil boots, and refit the coils.

Afterwards, clear any codes and road-test. If a misfire remains on the same cylinder, swap coils between cylinders to confirm the fault follows the coil. Keeping the plug wells dry, the rocker cover gasket sealed, and using decent parts will keep a 2004 Territory running sweet as for years.

Popular questions about 2004 Ford Territory ignition coils

How many ignition coils does a 2004 Ford Territory have?
The 2004 Territory’s 4.0‑litre Barra six uses six individual coil-on-plug units—one coil per cylinder. This design improves spark control and reduces lead/plug wire issues compared with older coil-pack setups.

What are common signs of a failing ignition coil on a 2004 Territory?
Typical signs include rough idle, stumbling on acceleration, poor fuel economy, hard starts, and a check engine light with misfire codes. Oil in the spark plug tubes from a weeping rocker cover gasket is a frequent culprit that accelerates coil failure.

Should all six coils be replaced at once?
If the vehicle has higher kilometres and one coil has failed, many techs recommend replacing the full set to avoid repeated labour and intermittent misfires. On lower‑km cars with a single confirmed faulty coil, a targeted replacement can be fine—just inspect the rest closely.