Replacing spark plugs (VW Golf 4)

Tools needed to remove the spark plug and adjust the gap

Measuring spark plug gap with a wire gauge

Measuring spark plug gap with feeler gauge

Correct functioning of spark plugs is one of the most important conditions for efficient engine operation. It is necessary that only the prescribed type of spark plugs are installed on the engine. If the engine is in good condition, cleaning the spark plugs is a rare operation.

All engines

Visual inspection of the working part of the spark plugs can show the condition of the engine. If the nose of the spark plug insulator is clean and white, without any deposits, this indicates that the mixture is too lean. This also indicates that the plug is too hot, i.e. the heat from the central electrode is slowly removed. If this is the case, it is necessary to adjust the fuel mixture or replace the plug.

If the nose of the insulator is covered with a black coating, this indicates that the mixture is too rich. If the coating is black and oily, this indicates engine wear and the need for inspection and repair. If the nose of the insulator is covered with a light brown coating, the mixture composition is optimal and the engine is in good condition.

The spark plug gap is very important because if the gap is too big or too small, the spark size changes, which leads to a decrease in engine efficiency. The gap must always meet technical requirements.

The gap is checked using a wire template (see figure Measuring spark plug gap with wire gauge) or with a feeler gauge (see figure Measuring spark plug gap with feeler gauge). The gap is adjusted by bending the side electrode. The central electrode should never be bent, as this can cause the insulator to break and the spark plug to fail.

To bend the side electrode of the spark plug, you need to use a special tool (see figure Tools needed to unscrew the spark plug and adjust the interelectrode gap).

Before installing the spark plug into the engine, check that the threads are clean and all threads are intact.


Screw in the spark plugs by hand and then tighten them to the specified torque.

Connect the high-voltage wires to the spark plugs.

Engine 1.4-I

1. Using special pliers or the HAZET 1849 device, remove the high-voltage wire tips from the spark plugs.

2. Clean the spark plugs using a brush, vacuum cleaner or compressed air to prevent dirt from getting into the engine cylinders after the spark plugs are removed. Unscrew the spark plugs using a spark plug wrench.

Engine 1.6-I

1. Using a screwdriver blade, remove the plugs covering the nuts securing the upper engine casing. Unscrew the nuts and remove the upper engine casing (the arrows indicate the location of the screws (A) securing the upper casing).



2. Using a screwdriver blade, remove the plugs covering the nuts securing the second engine casing. Unscrew the nuts (arrows) and remove the second engine casing.



3. Using special pliers or the HAZET 1849 device, remove the tips (arrows) of the high-voltage wires from the spark plugs.

4. Clean the spark plugs using a brush, vacuum cleaner or compressed air to prevent dirt from getting into the engine cylinders after the spark plugs are removed. Unscrew the spark plugs using a spark plug wrench.

Engine 1.8-I

1. Unscrew the nuts and remove the upper engine cover.



2. Unscrew the screws (1) securing the ignition coils (2).

3. Disconnect the electrical connectors from the ignition coils and remove the ignition coils from the spark plugs.

4. Clean the spark plugs using a brush, vacuum cleaner or compressed air to prevent dirt from getting into the engine cylinders after the spark plugs are removed. Unscrew the spark plugs using a spark plug wrench.

Engines 2.3-I (5 cylinders)

1. Open the hood.

2. Mark the high-voltage wires with numbers and remove the high-voltage wire caps from the spark plugs.

The information is available on the website: VWMANUAL.ru

3. Clean the spark plugs using a brush, vacuum cleaner or compressed air to prevent dirt from getting into the engine cylinders after the spark plugs are removed. Unscrew the spark plugs using a spark plug wrench.