AUTO·REPARE FR
Ignition

Spark plugs

The spark on a petrol engine. Diesel uses glow plugs, not these.

Teaching inline-four schematic. Not a specific car. Plugs

What it does

One per cylinder, under the coils here. Teaching petrol 8-valve, port injection schematic.

Screwed into the head.

Not a diagnosis. Interval and part number: the manufacturer’s schedule.

Common signs

  • Cold misfires, rough idle, check-engine light.

Already on the site

No generic spark-plug article on the site yet. Interval: plug type + the book — no single mileage.