Checking compression

Special tools and workshop equipment required

• T-bar and socket, 10 mm - 3220-

• Compression tester - V.A.G 1763- with adapter - V.A.G 1763/8-

Prerequisites for check

• Engine oil temperature min. 80°C
• Battery voltage at least 12.5 V.

Test sequence

• Remove engine cover panel ⇒ 3 Engine cover panel.

• Detach electrical connector from fuel pressure regulating valve - N 276- -arrow- at fuel rail.
• Start engine briefly to reduce fuel pressure in fuel rail.

• Remove all glow pin plugs using jointed spanner - 3220- ⇒ 28 – Glow plug system.
• Screw in adapter - V.A.G 1763/8- in each place where glow plugs were and connect compression tester - V.A.G 1763-.

• Have a 2nd mechanic operate starter until tester shows no further pressure increase.

Installation is carried out in the reverse order; note the following:

• Install glow plugs ⇒ 28 – Glow plug system.
• Entries are stored in the event memory of the engine control unit because electrical connectors were disconnected and the

  engine was started: Read event memory in vehicle selfdiagnosis ⇒.