Get Supplysystem-fuelinjection Guide for Volkswagen Fox SUV Second Generation (2003-2021)

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

24 – Supply system - fuel injection

1

Injection system - repair

General indications about the injection system

♦ The Engine control unit -J623- is equipped with self-diagnosis.

Before carrying out repairs and troubleshooting, always check

the fault memory first. Likewise, check vacuum hoses and

connections (air infiltration).

♦ Minimum voltage of 11.5V is necessary for the perfect opera‐

tion of electric components.

♦ Do not use sealants with silicone. Silicone component resi‐

dues aspired by the engine are not burned and damage the

Lambda Probe -G39- .

♦ Vehicles with airbag have a system for shutting off fuel in case

of an accident. This system should prevent fire in the vehicle

after an accident by disconnecting the Fuel pump (pre-supply

pump) -G6- through the Fuel pump relay -J17- . At the same

time, with this equipment, the engine starts more smoothly.

Fuel injection components - remove and install ⇒ page 87 .

Intake manifold - remove and install ⇒ page 89 .

Fuel distributor with injection valves - remove and install

⇒ page 90 .

Air filter set - disassemble and assemble ⇒ page 90 .

Air filter set - remove and install ⇒ page 91 .

Safety measures ⇒ page 92 .

Cleaning rules ⇒ page 65 .

Technical data ⇒ page 94 .

1. Injection system - repair

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1.1

Component location

A - Brake pedal switch -F47- or

Brake light switch -F-

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❑ Together in one case, in

the feet compartment,

on the brake pedal.

B - Accelerator pedal position

sensor -G79- and Sensor 2 of

accelerator pedal position -

G185-

❑ At the feet compart‐

ment, on the accelerator

pedal.

C - Clutch pedal switch -F36-

❑ In feet compartment, on

clutch pedal.

D - Fuel pressure regulator

❑ On the Fuel pump (pre-

supply pump) -G6- .

1 - Magnetic valve 1 for activa‐

ted charcoal filter tank -N80-

❑ In the engine compart‐

ment.

2 - Intake manifold

❑ Remove and install.

3 - Knock sensor 1 -G61-

❑ Installation location: On

engine block, intake

side.

4 - Engine control unit -J623-

❑ Below the lower wind‐

screen coating.

❑ Remove and install.

5 - Engine speed sensor -G28-

❑ Installation location: On engine block, intake side.

6 - Air intake temperature sensor -G42- with the Intake manifold pressure sensor -G71-

7 - Aeration hose valve

8 - Accelerator butterfly valve control unit -J338-

9 - Hall Sensor -G40-

10 - Coolant temperature sensor -G62-

11 - Air Filter

❑ Remove and install ⇒ page 91 .

12 - Oil pressure switch -F1-

13 - Lambda probe after the catalytic converter -G130-

14 - 4-pin connector

❑ Black

❑ To the Lambda probe -G39- Lambda probe heating -Z19- .

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Rep. Gr.24 - Supply system - fuel injection

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

15 - Lambda probe -G39-

16 - Ignition coil 1 with final power stage -N70- , Ignition coil 2 with final power stage -N127- and Ignition coil 3

with final power stage -N291-

17 - Fuel distributor

18 - Cylinder 1 injector - N30- , Cylinder 2 injector -N31- and Cylinder 3 injector -N32-

1.2

Fuel injection components - remove and install

1 - Air filter set

❑ With filtering element.

❑ Disassemble and as‐

semble ⇒ page 90 .

❑ Remove and install

⇒ page 91 .

2 - Duct for air aspiration

3 - Injection valve harnesses.

4 - Connector

❑ Black, 2 poles

❑ From Cylinder 1 injec‐

tion valve -N30 - .

❑ From Cylinder 2 injec‐

tion valve - N31- .

❑ From Cylinder 3 injec‐

tion valve - N32- .

5 - 10 Nm

6 - Fuel distributor with injec‐

tion valves

❑ Remove and install

⇒ page 90 .

7 - 20 Nm

8 - 20 Nm

9 - Intake manifold

10 - Lambda probe -G39- , 50

Nm

❑ Lubricate only the

thread with High-tem‐

perature paste -G 052

112 A3- ; High-tempera‐

ture paste -G 052 112

A3- should not enter in the grooves on the Lambda probe -G39- body.

❑ Remove and install with the Socket set for Lambda probe -3337- .

11 - Connector

❑ Black, 4 poles.

❑ From Lambda probe -G39- .

12 - Lambda probe after the catalytic converter -G130 - , 50 Nm

❑ Lubricate only the thread with High-temperature paste -G 052 112 A3- ; High-temperature paste -G 052

112 A3- should not enter in the grooves on the Lambda probe -G130- body, after the catalytic converter.

❑ Remove and install with the Socket set for Lambda probe -3337- .

13 - Connector

❑ Black, 4 poles.

1. Injection system - repair

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

❑ From Lambda probe after catalytic converter -G130 - .

14 - 10 Nm

15 - Coolant temperature sensor -G62-

❑ Before removing, eliminate, if necessary, cooling system pressure.

❑ 2-pole connector.

16 - Sealing ring

❑ Replace if damaged

17 - Retaining clip

❑ Check for proper seating.

18 - 10 Nm

19 - Thermostat valve body

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20 - Retaining clip

❑ Check for proper seating.

21 - Coupling connector

❑ Connect or disconnect the connector with ignition switched off.

22 - Engine control unit -J623-

❑ In case of replacement, it is necessary to adapt the Engine control unit -J623- to the Immobiliser control

unit -J362- ⇒ Vehicle diagnosis, testing and information system VAS 5051.

23 - Spring clamp

24 - Air duct

25 - From head cover

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Rep. Gr.24 - Supply system - fuel injection

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1.3

Intake manifold - remove and install

1 - 10 Nm

2 - Butterfly valve command

unit - J338-

❑ 6-pole coupling connec‐

tor.

❑ Golden contacts.

❑ Warmed Coolant.

❑ In case of replacement,

adapt the Engine control

unit -J623- to the Butter‐

fly valve command unit -

J338- ⇒ Vehicle diagno‐

sis, testing and informa‐

tion system VAS 5051.

3 - Gasket

❑ Replace.

4 - Coupling nozzle

❑ For oil separator.

5 - Coupling nozzle

❑ For the Electromagnetic

valve 1 for activated

charcoal filter -N80- .

6 - Sealing ring

❑ Replace if damaged

7 - 20 Nm

8 - 3 Nm

9 - Intake manifold pressure

sensor -G71- with Air temper‐

ature sensor -G42-

❑ 4-pole coupling connec‐

tor.

❑ Golden contacts.

10 - Sealing ring

❑ Replace if damaged

11 - 20 Nm

12 - Sealing ring

❑ Replace if damaged

13 - Intake manifold

14 - Intake nozzle

1. Injection system - repair

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1.4

Fuel distributor with injection valves - remove and install

1 - Fuel distributor with injec‐

tion valves

❑ Check injection valves

for tightness and flow

⇒ page 95 .

2 - Sealing ring

❑ Replace.

❑ Quickly lubricate with

engine clean oil before

installation.

3 - For cylinder 1 injection

valve -N30 -

❑ For cylinder 2 injection

valve -N31- .

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❑ For cylinder 3 injection

valve -N32- .

❑ Check injection valves

for tightness and flow

⇒ page 95 .

4 - Retaining clip

❑ Ensure proper seating

on injection valve and

fuel distributor.

5 - Drainage valve

❑ Drain the air

⇒ page 78 .

6 - 10 Nm

1.5

Air filter set - disassemble and assemble

Note

♦ For fastening the upper part of the air filter to the lower part, a

number of self-tightening bolts are used. If these bolts are

tightened or loosened with a power screwdriver, the thread on

the lower part of the filter can be damaged.

♦ For that reason, a power screwdriver is allowed only if:

♦ the power screwdriver speed does not exceed 200 rpm

♦ a torque of 1.6 Nm at most is adjusted.

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Rep. Gr.24 - Supply system - fuel injection

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1 - Upper part of filter air

2 - 1.6 Nm

3 - Filtering element

4 - Lower part of filter air

5 - 8 Nm

6 - Metal bonded rubber sup‐

port

7 - 5 Nm

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8 - Rubber bearing

9 - Duct for air aspiration

10 - Rubber bearing

11 - Hose

❑ For engine cylinder

head cover.

12 - Clamp

❑ Remove with VAS

5024A or Standart type

clamp pliers -VW 5162- .

13 - Air duct

❑ To the Butterfly valve

command unit -J338- .

1.6

Air filter set - remove and install

Special tools and workshop equipment required

♦ VAS 5024A or Standart-type clamp pliers -VW 5162-

1. Injection system - repair

91

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1.6.1

Removal

– Pull off intake air duct -1-.

– Loosen spring clamp -2- with the VAS 5024A or Standart type

clamp pliers - VW 5162- and pull of air duct from the upper part

of filter air set.

– Remove the left bolt fastening the air filter set -arrow-.

– Tilt the Battery -A- cover forwards.

– Move the air filter set upwards.

– Remove air filter set.

1.6.2

Installation

– Seat air filter set on the rubber supports -arrows-.

– Press air filter set downwards onto the pins.

– Tighten fastening bolts to 8 Nm.

– Fasten the air duct with the spring clamp on the upper part of

the air filter set -2-.

– Install intake air duct on intake nozzle-1-.

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1.7

Safety measures

WARNING

Fuel system is under pressure! Wear protective goggles and

clothing, so as to avoid serious injuries and contact with the

skin. Before loosening tube junctions, place a cloth around the

union point. Then, eliminate pressure by pulling the flexible

tube off carefully.

To prevent injuries in people and/or destruction of the injection

and ignition system, take into consideration the following:

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Rep. Gr.24 - Supply system - fuel injection

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

♦ For safety reasons, before opening the fuel system, remove

fuse number 33 from fuse holder, as the Fuel pump (pre-sup‐

ply pump) -G6- can be activated.

♦ Do not touch nor disconnect ignition cables with the engine in

operation or upon start.

♦ Only connect or disconnect the_lkinjection and ignition system

cables, including measurement device cables, with the ignition

switched off.

If, in drive tests, it is necessary to use measurement and test de‐

vices, consider the following:

♦ The measurement and test devices must be fastened to the

back seat and operated by another mechanic from then on.

If the measurement and test devices are operated from the front

passenger seat, the person seating there could be injured by the

passenger airbag being triggered, in case of an accident.

♦ To make the engine rotate with the starter, without running it:

– Disengage 4-pole connectors from Ignition coil 1 with final

power stage -N70- , Ignition coil 2 with final power stage -

N127- and Ignition coil 3 with final power stage -N291-

-arrows-.

– Disconnect coupling connectors -arrows- from cylinder 1 in‐

jector -N30- , cylinder 2 injector -N31- and cylinder 3 injector -

N32- .

– Remove fuse 33 from fuse holder.

1.8

Cleaning rules

To carry out fuel supply/injection works, consider the following “5

cleaning” rules thoroughly:

1. Injection system - repair

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

♦ Carefully clean union points and respective surrounding areas

before separating thm.

♦ Place parts on clean surface and cover them. Do not use

cloths that fray!

♦ Carefully cover or close open parts, in case repair is not carried

out immediately.

♦ Install clean parts only: Remove parts from the packaging im‐

mediately before installation. Do not use parts that have been

kept out of the packaging (for example, in tool boxes).

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♦ With system open: Do not work wit compressed air. Do not

move the vehicle.

1.9

Technical data

Engine identification letters

BMD/CHFB

650...870⁹⁾

Idle speed check

Idle speed operation ¹⁰⁾

Engine control unit -J623- ¹¹⁾

System

rpm

Simos 3PG⁸⁾

⇒ CPE (Electronic parts catalogue)

from about 5800

Part number

Engine speed regime limit

8) Simos 3 PG installed up to week 29, Simos 9.1 started in week 30.

9) Current values: ⇒ Inspection of exhaust gases

10) Not adjustable.

11) Remove and install Engine control unit -J623- ⇒ page 102 .

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Rep. Gr.24 - Supply system - fuel injection

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2

Check components

Check injection valves ⇒ page 95 .

Check fuel pressure regulator and residual pressure

⇒ page 98 .

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2.1

Injection valves - check

Special tools and workshop

equipment required

♦ Torque wrench - 5 to 50 Nm

(enc. 1/2") -VAG 1331-

♦ Remote control -VAG

1348A-

♦ Auxiliary measuring cable

set - VAG 1594C-

♦ Flow comparison meter -

VAG 1602-

2.1.1

2.1.2

Injection valve flow and tightness -

check

Check conditions

•

Fuel pressure must be OK ⇒ page 98 .

•

Residual pressure and fuel pressure regulator - check

⇒ page 98 .

2. Check components

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2.1.3

Checking process

– Remove 2-pole connector from the Cooling system tempera‐

ture sensor -G62- -arrow-.

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– Connect the Digital potentiometer (included at VAG 1594C) -

VAG 1630- to 1+2 contacts of the connector for coolant tem‐

perature sensor -G62 - and adjust the connected side to 15

kO.

– Remove supply hose in the fuel distributor -1- and install it over

the oil separator -2- hose.

– Remove injection valve harness -3- from fuel distributor bear‐

ings.

– Remove bolts fastening the fuel distributor-4-.

– Disengage ignition coil connectors -5-.

2.1.4

2.1.5

Tightness - check

Check conditions

•

Fuel distributor removed from cylinder head.

– Keep a container below the injection valves with the connec‐

tors removed.

– Ask someone else to operate the starter motor.

Fuel loss cannot exceed 2 drops a minute.

If the fuel loss is greater:

– Turn the ignition off.

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Rep. Gr.24 - Supply system - fuel injection

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

– Replace damaged injection valve ⇒ page 90 .

Injection valves are installed in the reversed order. Please note

the following:

•

All of the injection valve sealing rings must be replaced and

slightly lubricated with clean engine oil.

•

Install the fuel distributor, with injection valves locked, on the

intake manifold and fasten it evenly.

2.1.6

Injection valve flow - check

– Connect one injection valve contact, to be checked, to the

motor earth strap with Auxiliary measuring cable set -VAG

1594C- .

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– Connect the other injection valve contact with Remote control

-VAG 1348/3A- and Adapting cable -VAG 1348/3-2- to the

Battery - A- positive terminal.

– Turn ignition on; Fuel pump (pre-supply pump) -G6- must

work:

– Remove three graduated containers from the Flow compari‐

son meter -VAG 1602- .

– Remove fuel distributor from intake manifold.

– Place the injection valve to be checked in a graduated con‐

tainer.

– Remove the connectors from the injection valves that are not

being tested.

– Activate the Remote control -VAG 1348/3A- once more for 30

seconds.

– Do the same for the remaining injection valves.

Note

Use one graduated container for each injection valve.

– After all injection valves have been tested, place graduated

containers over a flat surface and compare the injection flow.

Nominal value: 85...91 ml per each valve.

If the measured values of one or more injection valves are above

or below the nominal value:

– Replace damaged injection valve.

2. Check components

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2.2

Residual pressure and fuel pressure regulator - check

Special tools and workshop

equipment required

♦ Pressure gauge -VAG

1318-

♦ Adapter -VAG 1318/9-

♦ Adapting set -VAG

1318/17-

♦ Connector -VAG 1318/23-

♦ Remote control -VAG

1348A-

♦ Adapting cable -VAG

1348/3-2-

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2.2.1

Pressure - check

Note

♦ The fuel pressure regulator establishes the approx. pressure

of 3.0 bar for vehicles manufactured until May/2006 and 4.0

bar for the ones produced as of June/2006.

♦ The fuel pressure regulator is on the Fuel pump (pre-supply

pump) -G6- .

2.2.2

Checking process

– Remove fuse holder cover.

– Remove fuse 33 from the ( Fuel pump (pre-supply pump) -

G6- ) fuse holder.

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Rep. Gr.24 - Supply system - fuel injection

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

WARNING

Fuel system is under pressure! Wear protective goggles and

clothing, so as to avoid serious injuries and contact with the

skin. Before loosening tube junctions, place a cloth around the

union point. Then, eliminate pressure by pulling the flexible

tube off carefully.

– Disconnect fuel hose coupling-1- and clean the spilled fuel

with a cloth.

Note

To unblock the fuel hose coupling, press the safety key.

– Install the Pressure gauge -VAG 1318 - with the Adapters -

VAG 1318/9- and Adapting set -VAG 1318/17- .

– Open the Pressure gauge -VAG 1318- valve. The valve indi‐

cates the flow direction.

– Put fuse 33 ( Fuel pump (pre-supply pump) -G6- ) in the fuse

holder again.

– Start engine and let it run in idle speed.

– Measure fuel pressure. Nominal value: 3.0 bar for vehicles

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manufactured until May/2006 and 4.0 bar for the ones pro‐

duced as of June/2006.

If the nominal value is not obtained:

– Turn the ignition off.

– Verify Fuel pump (pre-supply pump) -G6- ⇒ page 77 check

valve.

If nominal value is obtained:

– Turn the ignition off.

– Check tightness and residual pressure (of the whole system).

To do so, check the pressure drop on the Pressure gauge -

VAG 1318- . After 10 minutes, there must still be a positive

pressure of at least 2.0 bar.

If retaining pressure drops below 2 bar:

– Start the engine and run it at idle speed.

2. Check components

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FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

– Switch ignition off, after pressure has been created. At the

same time, it is necessary to close the Pressure gauge -VAG

1318- valve (valve transverse to the passage direction

-arrow-)

– Check pressure drop on the Pressure gauge -VAG 1318- .

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If pressure keeps dropping:

– Check Pressure gauge -VAG 1318- pipes to the Fuel pump

(pre-supply pump) -G6- .

– Check the tightness of the Pressure gauge -VAG 1318- .

If the pressure does quit dropping:

– Check sealing rings between fuel distributor and injection

valves and the hose between Pressure gauge -VAG 1318- and

fuel distributor.

Note

Before removing the Pressure gauge -VAG 1318- , place again

cloths around the hose connections.

2.2.3

2.2.4

Fuel pressure regulator - check

Check conditions

•

Retention valve for Fuel pump (pre-supply pump) -G6- OK,

check ⇒ page 77 .

2.2.5

Checking process

– Turn the ignition off.

– Remove fuse holder cover.

– Remove fuse 33 from the ( Fuel pump (pre-supply pump) -

G6- ) fuse holder.

– Connect the Remote control -VAG 1348/3A- and Adapter ca‐

ble -VAG 1348/3-2- to the lower contact of fuse 33 for activat‐

ing the Fuel pump (pre-supply pump) -G6- and to the positive

terminal of Battery -A- (+).

WARNING

Fuel system is under pressure! Wear protective goggles and

clothing, so as to avoid serious injuries and contact with the

skin. Before loosening tube junctions, place a cloth around the

union point. Then, eliminate pressure by pulling the flexible

tube off carefully.

– Loosen supply pipes -1- from fuel filter outlet.

– Return pipes-2- (blue), keep connected.

– Fuel filter-3- with inlet hose.

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Rep. Gr.24 - Supply system - fuel injection

Supplysystem-fuelinjection for Your Volkswagen Fox SUV Second Generation (2003-2021)

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