Porsche 996 TT Repair Manual page 632

• The battery voltage may not fall below 12 volts during the fuel pressure check!
1. Check the charge state of the battery, e.g. using a voltmeter or the Porsche System Tester PST 2. The
battery voltage must not fall below 12 volts during the check.
2. Connect the Porsche Tester PST 2 in the vehicle, switch on the ignition and switch off all loads,
such as the radio and air conditioning.
3. Remove the rear and middle underside panels. To remove the rear panel, the left side panel must also be
loosened, see ' 911 Carrera (996), 51 90 19 Removing and installing underside panels , position 4, 5 and
9.
4. Loosen the rapid−action coupling on the fuel return line −arrow− ; to do this, press in the locking
lug and pull off the coupling. Collect emerging residual fuel with a cloth, for example.
5. Insert receptacle into the open end of the hose for the special tool connection hose 9507 and connect with
the rapid−action coupling of the fuel return line. Be sure that the coupling is fitted correctly (must engage
audibly) by pulling the line apart!
6. Put the open end of the hose in a petrol−resistant canister. Keep a stopwatch at hand for the following
measurement.
7. Activate the fuel pump relay using the Porsche System Tester PST 2. To do this, select the line drive
links in the DME control unit individual search and then select fuel pump relay. Activate by pressing
F8 −see figure− . After 30 seconds, deactivate the relay again by pressing F8 .
8. Transfer the collected fuel into a suitable measuring cup.
Target value for supplied fuel quantity:
− in 30 seconds, at least 1.25 litres
9.
20 66 01 Checking quantity delivered by fuel pump
einordnung
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