Volkswagen New Beetle. Manual - part 1755

Fig. 16: Attaching Fuel Pressure Gauge To Check Fuel Pump Volume
Courtesy of VOLKSWAGEN UNITED STATES, INC.

2. Open shut-off valve on fuel pressure gauge. Lever points in direction of flow. See A in Fig. 16 .

3. Remove fuse No. 28 in fuse panel behind far left side of dash. See Fig. 3 . Connect VAG1348/3A remote

control to fuse 28 socket. Connect one end to B+ and other to appropriate fuse socket cavity. See Fig. 17 .
While operating VAG1348/3A remote control to run fuel pump, close shut-off valve slowly until gauge
reads 44 psi (3 bar) on all engines except 2.0L with engine codes BEV and BGD. On 2.0L engine codes
BEV and BGD, close shut-off valve slowly until gauge reads 51 psi (3.5 bar). Do not change position of
shut-off valve (leave shut-off valve in closed position). Empty fuel measuring container.

Fig. 17: Connecting Remote Control VAG 1348/3A With Adapter Cable VAG 1348/3-2 To Fuse
Block
Courtesy of VOLKSWAGEN UNITED STATES, INC.

2003 Volkswagen New Beetle GLS

1998-2003 ENGINE PEFORMANCE Basic Diagnostic Procedures - Beetle - Gasoline

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:43:30 AM

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Connect DVOM to battery. Operate remote control for 30 seconds. Record battery voltage.

5. Check fuel pump volume and compare to specification. See Fig. 18 . Voltage shown on graph in Fig. 18

is voltage at fuel pump. Subtract 2 volts from battery voltage to estimate fuel pump voltage. Fuel pump
volume shown is minimum delivery in 30 seconds.

Fig. 18: Determining Fuel Pump Volume In 30 Seconds (Voltage Measured At Fuel Pump Shown; 2
Volts Less Than Battery Voltage)
Courtesy of VOLKSWAGEN UNITED STATES, INC.

6. If minimum deliver rate is NOT as specified, check fuel filter and lines for possible restrictions (kinks) or

blockages. Pull fuel supply hose off inlet to fuel filter. Connect fuel pressure gauge between fuel supply
line and fuel filter. See Fig. 19 .

NOTE:

Quantity of fuel delivered depends on battery voltage. Voltage at fuel
pump is about 2 volts less than battery voltage.

2003 Volkswagen New Beetle GLS

1998-2003 ENGINE PEFORMANCE Basic Diagnostic Procedures - Beetle - Gasoline

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:43:30 AM

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Fig. 19: Testing Fuel Filter For Restrictions
Courtesy of VOLKSWAGEN UNITED STATES, INC.

7. Repeat fuel pump volume check. If minimum fuel delivery rate is now correct, replace fuel filter.

8. If minimum fuel delivery rate is NOT correct, remove fuel pump assembly from fuel tank and check for

restricted strainer filter. If strainer filter is not restricted, replace fuel pump.

FUEL PUMP CHECK VALVE

NOTE:

Fuel pump can be removed from inside vehicle. Remove cover in floor pan
under rear seat to access fuel pump/sending unit assembly.

CAUTION: Models with airbag are equipped with crash fuel shut-off system. Fuel

shut-off system reduces danger of fire in a crash when fuel pump is
switched off via fuel pump relay. At the same time this system improves
starting of the engine. When the door is opened the fuel pump is activated

2003 Volkswagen New Beetle GLS

1998-2003 ENGINE PEFORMANCE Basic Diagnostic Procedures - Beetle - Gasoline

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:43:30 AM

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1. Remove fuel filler cap. Connect VAG1318 pressure gauge with adapters, or equivalent, to fuel supply

line on fuel rail. Do not connect pressure gauge to fuel rail. Place fuel pressure gauge line in a fuel
measuring container. See Fig. 16 .

2. Close shut-off valve on fuel pressure gauge. Lever is at right angles to direction of flow. See B in Fig.

16 .

3. Remove fuse No. 28 in fuse panel behind far left side of dash. See Fig. 3 . Connect VAG1348/3A remote

control to fuse 28 socket. Connect one end to B+ and other to appropriate fuse socket cavity. See Fig. 17 .
Operate VAG1348/3A remote control until pressure gauge reads 44 psi (3 bar). If pressure builds up too
high, bleed off until correct pressure is obtained.

4. Watch pressure on fuel gauge. Pressure may not drop below 36.2 psi (2.5 bar) after 10 minutes. If the

pressure continues to drop, check line connections for proper sealing. If fuel lines are okay, replace fuel
pump.

FUEL PUMP CURRENT DRAW

If fuel pump pressure and volume are correct, but fuel pump circuit problem is suspected, check fuel pump
current draw.

Fuel pump current draw can be checked at fuel pump assembly unit 4-pin connector under access cover. See
Fig. 20 . Maximum fuel pump current draw is 8 amps. If fuel pump current draw is too high, replace fuel pump.
For fuel pump wiring, see appropriate ENGINE PERFORMANCE wiring in SYSTEM WIRING DIAGRAMS
in ELECTRICAL.

for 2 seconds to build up the pressure in fuel system.

WARNING:

Fuel system is under pressure. Before opening fuel system place cloth
around connection. Then release pressure by carefully loosening
connection. Always wear eye protection and wear fuel-resistant gloves
when disconnecting fuel system connections.

NOTE:

Fuel pump can be removed from inside vehicle. Remove cover in floor pan
under rear seat to access fuel pump/sending unit assembly.

NOTE:

Fuel pump assembly access cover is under rear seat. It is not necessary to
remove fuel tank to remove fuel pump.

2003 Volkswagen New Beetle GLS

1998-2003 ENGINE PEFORMANCE Basic Diagnostic Procedures - Beetle - Gasoline

Helpmelearn Repair Manuals

Wednesday, December 14, 2005 8:43:30 AM

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