Checking spark plugs (Opel Insignia A)

1. Make sure the correct spark plugs are used in the vehicle. Using the wrong spark plugs may cause the engine to run rough.

2. Make sure that the spark plugs have the correct heat setting. Using spark plugs with the wrong heat setting can lead to the following consequences:

• spark plug fouling - colder plugs;
• pre-ignition and/or engine damage - hotter spark plugs.

3. Visually inspect the spark plugs for damage.

4. Perform engine diagnostics based on the condition of the spark plugs, as described in Chapter 2 of this manual.

Material copied from this resource [opelbook]