Measuring compression in cylinders (VW Golf 1)

Measuring the compression in the engine cylinders will provide information on whether the valves and piston rings are well sealed. This affects the power, cold start characteristics, oil and fuel consumption, and smoke formation of the diesel engine. Thus, thanks to the compression diagram, we get a good idea of the mechanical condition of the diesel engine.

The measurement is carried out as follows:

• The engine must be warm and in working order.
• Remove and insulate the wire at the high pressure fuel pump switch.
• Remove all high pressure pipelines and place them on a clean surface.
• Remove the injectors (see section "Removal injectors", chapter "Diesel injection system").
• Screw the test device with the adapter into the injector hole of the first cylinder; put the old thermal insulation seal underneath.
• Turn the crankshaft with the starter (gearbox lever in "neutral") until the value on the scale of the compression measuring device begins to increase further.
• Write down the specified value; then take measurements at the next cylinder.

Pressure values

Suction diesel and turbo diesel engines	Normal compression pressure	Min. allowable pressure	Max difference between cylinders
	34.0 bar	28.0 bar	5.0 bar