Compression check (VW Golf 1)

If the main engine mechanisms are heavily worn, adjustment may be useless - this is especially true for cars with high mileage. To assess the condition of the cylinders, piston rings and valves, you should check the compression, which in different cylinders should differ by no more than 10%. If the compression in the cylinders is below normal (see section "Technical data"), the engine will run unsteadily and will not develop sufficient power. To measure compression, use a compression gauge, which can be purchased at auto parts stores.

1. Warm up the engine to operating temperature and remove the high-voltage wires from the spark plugs. Remember to hold the wires by the spark plug cap, not by the wire itself. If the wires are not marked, mark them to avoid confusion during subsequent installation. Remove the spark plugs.

2. Disconnect the central high-voltage wire from the ignition distributor.

3. Insert or screw the compression tester into the spark plug hole of cylinder #1 (figure B:4) and ask an assistant to turn the engine with the starter, pressing the accelerator pedal all the way down. Turn the engine until the instrument readings stop increasing (at least two full revolutions of the crankshaft). Record the instrument readings.



4. Record the compression value and cylinder number.



5. Repeat the measurement on the remaining cylinders and record the results.

6. Compare the measurement results with the data in the section "Technical data". If the compression values are high enough and differ in different cylinders by no more than 10%, then the engine can be considered to be in good condition.

If the compression in one or two cylinders is lower than in the others, repeat the measurement by pouring some engine oil into the cylinder being tested through the spark plug hole. If the compression increases, this means that the piston rings or cylinder walls are worn or damaged. If the compression value remains the same, this indicates a leak in the valves or cylinder head gasket.

Measures to eliminate such malfunctions are described in the chapter "Engine...".