Information And Tools

Information 

• In the case of new engines that have not yet been fully run in (less than 5, 000 km), there may be higher pressure losses than after the run-in period as cylinders, pistons and piston rings have not yet attained their final dimensional stability. 
• Differences between the individual cylinders of up to two graduation lines = 4 % pressure loss are not significant. 

Assessing the problem: 

A pressure loss test can be carried out in order to determine the extent of the problem more precisely following a compression pressure test. The leak is located by listening for sounds of escaping air.

The following areas can be checked: 

Intake pipes (checking inlet valves)

Exhaust manifolds and exhaust pipes (checking exhaust valves)

Positive crankcase ventilation and oil filler neck (checking piston rings)

Coolant filler neck and spark plug bore of adjacent cylinder (checking cylinder-head gasket)

> VAS 522 001 - Pressure loss tester 

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Tools for testing pressure loss

1. Pressure gauge
2. Pressure-regulating valve on pressure gauge
3. Dead-centre gauge
4. Adapter M12 (1763/9 - 1) from > V.A.G 1763/9 - Porsche adapter set for compression tester Check valve must be removed for the pressure loss test. 

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Check valve in tool 1763

1. > V.A.G 1763/9 - Porsche Adapter Set for Compression Tester 
2. Adapter M12
3. Remove check valve using a tyre valve remover.