Table of contents: Removal ↓ Examination ↓
Removal
Caution! Unscrew the spark plugs only when the engine is cold or its temperature should be such that you can hold your hand on it. When removing the spark plugs from a hot engine, you can damage the threads in the spark plug sockets, which are installed on the cylinder head, which is made of light metal.
1. Turn off the ignition.
2. Remove the engine protective cover.
Cars with V6 engine
3. Right cylinder head. Remove the air cleaner cover.
4. Left cylinder head. Unscrew the coolant expansion tank from the bracket and, without disconnecting the hoses, move it away from the work area.
5. Remove clamp 1, unscrew bolt 2 (see illustrations 17.5, 17.5a).
17.5. Remove clamp 1, unscrew bolt 2. Right cylinder head |
17.5a. Remove clamp 1, unscrew bolt 2. Left cylinder head |
6. Disconnect the spark plug connectors.
7. Remove the ignition coils.
8. Unscrew the spark plugs using a spark plug wrench.
Cars with V8 engines
9. Disconnect plugs 1 from the ignition coils (see illustrations 17.9 and 17.9a).
17.9. Disconnect plugs 1 from ignition coils. Left cylinder head |
17.9a. Disconnect plugs 1 from ignition coils. Right cylinder head |
10. Unscrew bolts 2 and remove the bracket (see illustrations 17.9 and 17.9a).
11. Unscrew the 3 bolts securing the ignition coils (see illustrations 17.9 and 17.9a) and remove the coils.
12. Unscrew the spark plugs using a spark plug wrench.
Installation of spark plugs is carried out in the reverse order of removal.
Examination
13. Inspect the spark plugs. If the spark plug is oily, then there is a misfire or it is caused by poor condition of the piston rings of the corresponding cylinder (check the compression by contacting a workshop).
14. Check the gap between the electrodes using a template, for example, HAZET 2147 MS (see illustration).
The gap between the spark plug electrodes is 1.0±0.1 mm.
Attention! The gap between the electrodes of new spark plugs is usually set correctly at the manufacturer. It can only be checked, but not corrected. If the gap between the electrodes exceeds the nominal value, the spark plug should be replaced with a new one.
(The text is based on materials from the website «AudiManual.ru»)