Checking Fuel Pressure

Special Tools:

No. Designation Special tool Explanation
A Pressure gauge P 378a
B Connection line 9559

Checking fuel pressure

Checking
1. Undo covering cap on test connection of fuel collection pipe and remove.
2. Connect pressure gauge (special tool P 378a) with connecting line (special tool 9559) and connect to test connection.







3. Actuating fuel pump with Porsche System Tester 2:
The fuel pump can be actuated with the Porsche System Tester 2 or by bridging the fuel-pump relay.

Via fuel-pump relay without Tester:
Disconnect fuel-pump relay from the central electrical board and bridge contacts 30 and 87 (identified as 3 and 5 on the central electrical board) with a fused shop-made cable. The fuel pump must now operate or deliver fuel.







4. Nominal test values:
Stationary engine: 3.8 ± 0.2 bar
Engine idling: 3.3 ± 0.2 bar


NOTE:
The seal or sealing ring in the brass closure cap is not exchangeable. It must therefore be used only once.

Tightening torque of new brass closure cap 2.5 ± 0.5 Nm (2.0 ± 0.5 ft. lbs.).