CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– If the sender cannot be released in this way, the retaining tabs
-arrows- must also be pushed to the side slightly.
– Note colour co-ordination of cables for reinstallation.
– Release electrical connectors -1 to 3- and pull them off. Then
bend back locking lugs of connectors.
Installing:
– Connect connectors -1…3-. Observe colour co-ordination.
– Check connectors are secured properly by pulling.
– Insert fuel gauge sender - G- into guide on fuel delivery unit
and press down until it engages.
– Install fuel delivery unit ⇒ page 346 .
8.3
Checking fuel pump - G6-
350
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CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
Special tools and workshop
equipment required
♦ Pressure gauge - VAS 6550-
♦ Remote control - V.A.G 1348/3A-
♦ Test instrument adapter/DSO (5-pin) - VAS 5565-
♦ Multimeter - V.A.G 1715-
♦ Special wrench - T10202-
♦ Torque wrench - V.A.G 1332-
♦ Measuring container, capacity: 3 litres
8.3.1
Checking function and voltage supply
Test conditions:
•
•
•
Battery voltage at least 11.5 V.
Fuse for Fuel pump control unit - J538- OK.
Fuel pump control unit - J538- OK.
8. Repairing fuel supply system (Golf, Eos, Scirocco)
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Test sequence
Note
♦ Function of fuel pump is checked using final control diagnosis.
♦ If the final control diagnosis is to be carried out several times
in succession, it may be necessary to start the engine briefly
before repeating the final control diagnosis.
– Connect vehicle diagnostic tester as follows:
– Push diagnosis cable connector onto diagnosis connection in
driver footwell.
– Switch ignition on.
– Press buttons on display one after the other for Vehicle
self-diagnosis, Engine electronics and Final con-
trol diagnosis.
– Press right arrow button ► on display up to final control diag‐
nosis for fuel pump electronics.
The fuel pump must now run slowly up to maximum speed.
Note
The fuel pump runs very quietly.
– Switch off ignition.
If fuel pump does not run:
– Remove bench seat ⇒ General body repairs, interior; Rep. gr.
72 ; Removing and installing bench seat .
– Pull connector off fuel pump control unit - J538- .
– Check voltage supply between contacts -1- and -6- using mul‐
timeter - V.A.G 1715- .
•
Specification: approx. battery voltage
Voltage supply not OK:
– Locate and eliminate open circuit referring to current flow di‐
agram ⇒ Current flow diagrams, Electrical fault finding and
Fitting locations.
Voltage supply OK:
352
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4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Remove cover -1- with fuel pump control unit - J538- -2- from
fuel delivery unit.
– First check that the connector -arrow- is fitted securely by pull‐
ing the connector without pressing the catch. If connector was
not inserted correctly, repeat functional check of fuel pump.
– Now pull off connector.
– Check the contacts on the connector and on the fuel delivery
unit for damage.
WARNING
Fuel supply line is pressurised. Wear protective goggles and
protective clothing to avoid injury and contact with the skin.
Wrap a cloth around the connection before loosening hose
connections. Then release pressure by carefully pulling hose
off connection.
– Pull fuel lines -1- and -2- off the flange.
Note
♦ Press in securing ring to release the fuel lines.
♦ On vehicles with auxiliary heater, the connector and the fuel
line of the metering pump - V54- must also be disconnected.
– Open locking ring using key - T10202- .
Caution
Do not cant key - T10202- and press against locking ring firmly.
If the key slips off, the fuel delivery unit can be damaged.
– Check that electrical wires between flange and fuel pump are
connected.
If no open circuit can be found:
– Fuel pump defective, renew fuel delivery unit ⇒ page 346 .
8. Repairing fuel supply system (Golf, Eos, Scirocco)
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8.3.2
Checking fuel pressure
Note
♦ The fuel pressure must be checked by means of the final con‐
trol diagnosis. If the fuel pressure is measured at idling speed,
it may deviate from the specification.
♦ If the final control diagnosis is to be carried out several times
in succession, it may be necessary to start the engine briefly
before repeating the final control diagnosis.
WARNING
Fuel supply line is pressurised. Wear protective goggles and
protective clothing to avoid injury and contact with the skin.
Wrap a cloth around the connection before loosening hose
connections. Then release pressure by carefully pulling hose
off connection.
– Pull off supply line (metal coupling) -arrow- and catch escaping
fuel with a cloth.
Note
Press in securing ring to release fuel line.
– Connect pressure tester - VAS 6550- to fuel supply line with
adapter - VAS 6550/1- and -VAS 6550/2- .
– Make sure that drain tap is closed and cut-off taps are open.
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– Read fuel pressure on pressure gauge.
•
Specification: 4.0 to 7.0 bar
If fuel pressure is OK, check holding pressure ⇒ page 358 .
If the specification is exceeded:
– Check return line between fuel filter and fuel pump for kinks
and blockages.
If no fault is found:
– Pressure limit valve in fuel filter is defective. Renew fuel filter.
If specification is not obtained
– Check fuel pressure upstream of fuel filter; proceed as follows:
354
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CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Pull fuel supply line -arrow- off fuel filter.
– Connect pressure tester - VAS 6550- between fuel filter and
fuel supply line with adapter - VAS 6550/1- and -VAS 6550/2- .
– Make sure that drain tap is closed and cut-off taps are open.
– Switch ignition on and activate the fuel pump with the final
control diagnosis function.
– While the fuel pump is operating, close the shut-off tap -A-.
Pressure must rise to at least 7.0 bar. When 7.0 bar is reached,
open shut-off tap again immediately.
If pressure has risen:
– Fuel pump is OK. Pressure limiting valve in fuel filter is defec‐
tive. Renew fuel filter.
If pressure does not rise:
– Fuel pump defective, renew fuel delivery unit ⇒ page 346 .
8. Repairing fuel supply system (Golf, Eos, Scirocco)
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8.3.3
Checking fuel pressure when the engine
is running (engine codes CCZA, CCZB,
CDAA, CDAB)
Note
♦ If a complaint is made about the vehicle's performance, the
reason may be that the fuel pressure is too low. Faults in the
high-pressure section may also be caused by inadequate fuel
pressure in the low-pressure section. This check determines
the fuel pressure in the high-pressure and low-pressure sec‐
tions during a road test. Fuel pressure in the high-pressure
section is read from the engine control unit. The lowest fuel
pressure is measured by the pressure tester - VAS 6550- and
reported to the vehicle diagnosis and service information sys‐
tem - VAS 5052 B- .
♦ This test can be part of “Guided Fault Finding” if an entry has
been made in the event memory. However, it can also be star‐
ted in the vehicle diagnosis and service information system -
VAS 5052 B- by means of “Functions and component
selection”.
Special tools and workshop equipment required
♦ Pressure gauge - VAS 6550-
♦ Hose adapters - VAS 6550/1- and -VAS 6550/2-
♦ Vehicle diagnosis and service information system - VAS 5052
B-
♦ Connector cable - VAS 5051/66-
– Remove bench seat ⇒ General body repairs, interior; Rep. gr.
72 ; Removing and installing bench seat .
– Remove cover -1- with fuel pump control unit - J538- -2- from
fuel delivery unit.
– First check that the connector -arrow- is fitted securely by pull‐
ing the connector without pressing the catch. The connector
can cause a fault if it has not been fitted correctly.
WARNING
The fuel line is under pressure.
Fuel poses danger of injury to eyes and skin.
Wear protective goggles and protective clothing to avoid injury
and contact with the skin. Wrap a cloth around the connection
before loosening hose connections. Then reduce pressure by
carefully opening the connection.
356
Rep. gr.20 - Fuel supply system
CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Pull off supply line -arrow- and catch escaping fuel with a cloth.
Note
Press in securing ring to release fuel line.
– Connect pressure tester - VAS 6550- to fuel supply line with
adapter - VAS 6550/2- and -VAS 6550/1- .
– Fit connector cable - VAS 5051/66- to pressure tester - VAS
6550- and to vehicle diagnosis and service information system
- VAS 5052 B- .
– Make sure that drain tap is closed and cut-off taps are open.
– Switch on pressure tester - VAS 6550- .
If the fuel pressure test is carried out within “Guided Fault Find‐
ing”, follow the instructions of the diagnostic tester.
If the fuel pressure test is carried out without “Guided Fault Find‐
ing”, proceed as follows:
– Connect vehicle diagnosis and service information system -
VAS 5052 B- to vehicle.
– Select Guided Fault Finding in -VAS 5052 B- .
– Carry out identification of vehicle.
– Using the GoTo button, select the following menu options one
after the other:
♦ Function/component selection
♦ Drive
♦ Engine
♦ 24 Mixture preparation/injection
♦ Mechanical components
♦ High-pressure pump
– Follow instructions on vehicle diagnosis and service informa‐
tion system - VAS 5052 B- .
WARNING
Test instruments and measuring equipment must always be
secured to the rear seat and operated by a second person from
this location.
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8.3.4
Checking holding pressure
•
Fuel pressure OK and pressure tester - VAS 6550- connected.
Check fuel pressure ⇒ page 354 .
Test sequence
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– Read fuel pressure on pressure gauge.
•
Specification: 4.0 to 7.0 bar
– End self-diagnosis, and switch off ignition.
– Watch pressure drop on pressure gauge. Pressure must re‐
main above 3.0 bar for 10 minutes.
If the pressure drops further:
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– After pressure has built up, close cut-off tap -B- of pressure
tester immediately. Lever is then at right angle to direction of
flow.
If the pressure does not drop now (leak on engine side)
⇒ page 359 .
If the pressure drops again (leak on fuel tank side):
Leak must be sought on fuel tank side; proceed as follows:
– Check fuel supply line to fuel filter for leaks.
If no fault is found on the fuel line:
– Check pressure retention valve in fuel delivery unit. Proceed
as follows:
– Pull fuel supply line -arrow- off fuel filter.
358
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CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Connect pressure tester - VAS 6550- between fuel filter and
fuel supply line with adapter - VAS 6550/1- and -VAS 6550/2- .
– Make sure that drain tap is closed and cut-off taps are open.
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– Read fuel pressure on pressure gauge.
•
Specification: 4.0 to 7.0 bar
– After pressure has built up, close cut-off tap -A-.
– Watch pressure drop on pressure gauge. Pressure must re‐
main above 3.0 bar for 10 minutes.
If the pressure drops:
– Pressure retention valve in fuel pump defective; renew fuel
delivery unit ⇒ page 346 .
If the pressure does not drop:
– Pressure retention valve in fuel filter is OK, pressure limiting
valve in fuel filter is defective. Renew fuel filter.
If the pressure does not drop now (leak on engine side):
Note
Search for leak on engine side. Repeat holding pressure test. This
time, close shut-off tap -A- to check whether leak actually is on
engine side.
– If there is a leak on the engine side, carry out external check
of the fuel pipes and high-pressure pump for leaks.
If no fault can be determined, check the injectors for leaks:
– Remove spark plugs. Open shut-off valves -A- and -B-. Ac‐
tuate fuel pump with final control diagnosis.
– Check through spark plug holes whether fuel has collected on
the piston crown due to a leaking injector.
8.3.5
Checking fuel delivery rate (engine co‐
des CAWA, CAWB, CBFA, CCTA,
CCTB, BZB, CGYA)
– Remove bench seat ⇒ General body repairs, interior; Rep. gr.
72 ; Removing and installing bench seat .
8. Repairing fuel supply system (Golf, Eos, Scirocco)
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4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Remove cover -1- with fuel pump control unit - J538- -2- from
fuel delivery unit.
– First check that the connector -arrow- is fitted securely by pull‐
ing the connector without pressing the catch. The connector
can cause a fault if it has not been fitted correctly.
– Now pull off connector.
– Check the contacts on the connector and on the fuel delivery
unit for damage.
– Connect test instrument adapter/DSO (5-pin) - VAS 5565- to
connector and fuel delivery unit.
– Connect remote control - V.A.G 1348/3A- to adapter - VAS
5565- and to battery positive terminal clamp in the engine
compartment.
Note
This step serves only to have the fuel pump running when the
engine is stopped.
WARNING
Fuel supply line is pressurised. Wear protective goggles and
protective clothing to avoid injury and contact with the skin.
Wrap a cloth around the connection before loosening hose
connections. Then release pressure by carefully pulling hose
off connection.
– Pull off supply line (metal coupling) -arrow- and catch escaping
fuel with a cloth.
Note
Press in securing ring to release the fuel lines.
360
Rep. gr.20 - Fuel supply system
CC 2010 ➤ , Eos 2006 ➤ , Golf 2004 ➤ , Golf 2009 ➤ , Passat 2006 ➤ , ...
4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Connect pressure tester - VAS 6550- to fuel supply line with
adapter - VAS 6550/2- . Hold adapter - VAS 6550/1- in a
measuring container.
– Make sure that drain tap is closed and cut-off taps are open.
WARNING
Danger of spraying! Wear protective goggles and protective
clothing to avoid injury and contact with the skin. Hold container
in front of open connection of pressure tester.
– Operate remote control - V.A.G 1348/3A- . Then slowly close
shut-off tap -arrow- until a pressure of 4 bar is displayed on
pressure gauge. From this point on do not move position of
shut-off tap.
– Drain measuring container.
– The quantity delivered by the fuel pump depends on the bat‐
tery voltage. Therefore, also connect multimeter - V.A.G 1715-
to outputs -1 and 5- of test instrument/DSO adapter 5-pin -
VAS 5565- .
– Operate remote control for 60 seconds while measuring volt‐
age at fuel pump.
– Compare quantity of fuel delivered with specification.
*) Minimum delivery rate cm³/60 s
**) Voltage at fuel pump with engine not running and pump run‐
ning.
Reading example:
During the test a voltage of 10.5 volts is measured. This equates
to a minimum delivery rate of approx. 1200 cm³/60 s
If specification is not obtained
– Check fuel lines for possible restrictions (kinks) or blockages.
If no fault is found:
– Remove cap from fuel filler neck and repeat check. If fuel de‐
livery rate is now reached, check fuel tank breather.
If reading again does not match specification:
– Check fuel filter (proceed as follows):
WARNING
Fuel supply line is pressurised. Wear protective goggles and
protective clothing to avoid injury and contact with the skin.
Wrap a cloth around the connection before loosening hose
connections. Then release pressure by carefully pulling hose
off connection.
8. Repairing fuel supply system (Golf, Eos, Scirocco)
361
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4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Pull fuel supply line -arrow- off fuel filter.
– Connect pressure tester - VAS 6550- to fuel supply line with
adapter - VAS 6550/1- . Hold adapter - VAS 6550/2- in a
measuring container.
– Make sure that drain tap is closed and cut-off taps are open.
– Operate remote control - V.A.G 1348/3A- . Then slowly close
shut-off tap -arrow- until a pressure of 4 bar is displayed on
pressure gauge. From this point on do not move position of
shut-off tap.
– Drain measuring container.
– Repeat delivery rate check.
If the minimum delivery rate is now attained:
– Renew fuel filter.
If the minimum delivery rate is again not attained
– Remove fuel delivery unit and check filter strainer for soiling.
Only if still no fault has been detected:
– Renew fuel delivery unit.
If the fuel delivery rate has been attained but a fault is still sus‐
pected in the fuel supply system (e.g. intermittent failure of fuel
supply system):
– Measure current draw of fuel pump ⇒ page 364 .
8.3.6
Checking fuel delivery rate (engine co‐
des CCZA, CCZB, CDAA, CDAB)
Note
The fuel delivery rate must first be checked in the engine com‐
partment with the help of the function “Checking fuel delivery rate,
quick test”. If the minimum delivery rate is not achieved, a 2nd
measurement must be carried out at the flange of the fuel delivery
unit.
Checking fuel delivery rate in engine compartment:
– Connect vehicle diagnosis and service information system -
VAS 5052 B- to vehicle.
– Select Guided Functions in -VAS 5052 B- .
– Carry out identification of vehicle.
– Select Engine.
– Select Checking fuel delivery rate, quick test.
362
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4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– Follow instructions on vehicle diagnosis and service informa‐
tion system - VAS 5052 B- .
Checking fuel delivery rate at flange:
•
The guided function “Checking fuel delivery rate, quick test”
has been carried out ⇒ Vehicle diagnostic tester
•
The remote control - V.A.G 1348/3A- and test instrument
adapter/DSO (5-pin) - VAS 5565- have been connected to the
fuel delivery unit.
•
•
Battery charger connected
Filling level in fuel tank above reserve
Test sequence
WARNING
The fuel line is under pressure.
Fuel poses danger of injury to eyes and skin.
Wear protective goggles and protective clothing to avoid injury
and contact with the skin. Wrap a cloth around the connection
before loosening hose connections. Then reduce pressure by
carefully opening the connection.
– Pull fuel supply line -arrow- off fuel filter.
– Connect pressure tester - VAS 6550- to fuel supply line with
adapter - VAS 6550/1- . Hold adapter - VAS 6550/2- in a
measuring container.
– Make sure that drain tap is closed and cut-off taps are open.
– Operate remote control - V.A.G 1348/3A- . Then slowly close
shut-off tap -arrow- until a pressure of 4 bar is displayed on
pressure gauge. From this point on do not move position of
shut-off tap.
– Drain measuring container.
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– The quantity delivered by the fuel pump depends on the bat‐
tery voltage. Therefore, connect multimeter - V.A.G 1715- to
wires -1- and -5- of adapter - VAS 5565- in addition.
– Operate remote control for 60 seconds while measuring volt‐
age at fuel pump.
– Compare quantity of fuel delivered with specification.
*) Minimum delivery rate cm³/60 s
**) Voltage at fuel pump with engine not running and pump run‐
ning.
Reading example:
During the test a voltage of 10.5 volts is measured. This equates
to a minimum delivery rate of approx. 1200 cm³/60 s
If specification is not obtained
– Remove cap from fuel filler neck and repeat check. If fuel de‐
livery rate is now reached, check fuel tank breather.
If reading again does not match specification:
– Remove fuel delivery unit and check filter strainer for soiling.
– If no fault is found here either, renew flange with fuel filter.
– Repeat check.
If reading again does not match specification:
– Fuel pump defective, renew fuel delivery unit ⇒ page 326 .
If fuel delivery rate has been attained, but nevertheless you sus‐
pect a fuel supply system fault (e.g. intermittent failure of fuel
supply system): Check fuel pressure with the engine running
⇒ page 336 .
8.3.7
Checking current consumption
– Remove bench seat ⇒ General body repairs, interior; Rep. gr.
72 ; Removing and installing bench seat .
– Remove cover -1- with fuel pump control unit - J538- -2- from
fuel delivery unit.
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4-cyl. injection engine (1.8 and 2.0 l engine, chain drive) - Edition 08.2018
– First check that the connector -arrow- is fitted securely by pull‐
ing the connector without pressing the catch. The connector
can cause a fault if it has not been fitted correctly.
– Now pull off connector.
– Check the contacts on the connector and on the fuel delivery
unit for damage.
– Connect test instrument adapter/DSO (5-pin) - VAS 5565- to
connector and fuel delivery unit.
– Connect pick-up clamp -A- to red terminal with lettering “pick-
up clamp” for test instrument adapter/DSO (5-pin) - VAS
5565- .
– Start engine and run at idling speed.
– Measure current draw of fuel pump.
•
Specification: max. 9 amps
Note
♦ The starting current for the fuel pump can be briefly above
specifications when starting the engine.
♦ If the fault in the fuel system is not always evident, the check
can also be carried out during a road test. A 2nd person is
required to do this, however.
If the current draw is exceeded:
– Fuel pump defective, renew fuel delivery unit ⇒ page 346 .
8. Repairing fuel supply system (Golf, Eos, Scirocco)
365
2024 VW Passat Owner's Manual
VW Passat B7 Service & Repair Manual
VW Passat B6 Service & Repair Manual
