Compression, Checking

WARNING: This page is about a different car, the 2014 Volkswagen Jetta, 2013 Volkswagen Jetta, 2012 Volkswagen Jetta, and 2011 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The compression can also be checked using the Vehicle Diagnosis Tester.

Special tools and workshop equipment required

Compression Tester Kit VAG1763 with Compression Tester Kit - Adapter 8 VAG1763/8

Test Conditions

Engine oil temperature must be at least 30 °C (86 °F).
The battery voltage must be at least 12.7 volts.
All electrical consumers such as, lights and rear window defogger, must be turned off.

Test Sequence

-- Remove the glow plug from the corresponding cylinder. Refer to GLOW PLUG .

-- Install the Compression Tester Kit - Adapter 8 VAG1763/8 in place of the glow plug.

-- Check the compression pressure using the Compression Tester Kit VAG1763.

NOTE:

Using the tester, refer to the tester operating instructions.

-- Operate the starter until the tester show there is no further increase in pressure.

Compression Pressure

New: 25.0 to 31.0 bar (362.5 to 449.6 psi)
Wear limit: 19.0 bar (275.5 psi)
Permissible difference between all cylinders: maximum 5.0 bar (72.5 psi)

-- Install the glow plug to the corresponding cylinder. Refer to GLOW PLUG .

NOTE:

By disconnecting the connectors, Diagnostic Trouble Codes (DTCs) are stored to memory. After the test, check the fault memory and erase, if necessary.

-- Check the DTC memory of the Engine Control Module -J623- and erase all of the DTC entries. Refer to the vehicle diagnostic tester.