Fuel System - Repair Instructions BMW Z4 E85/E86

13 31... Notes on fuel pressure check (reference pressure: environment)

Feature of this version with ambient pressure

The connection for the vacuum hose of the fuel pressure regulator is located between the throttle and the air cleaner or on the air cleaner.

Test precondition

The correct fuel pressure regulator is fitted.

1. Using the EPC, check whether the fuel pressure regulator suitable for the car is fitted: Connect test adapter. See «13 31 029 Checking Fuel Pump Delivery Pressure (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-31-029-checking-fuel-pump)

Description of operation

The control function of the fuel pressure regulator must be guaranteed under all operating conditions. The fuel pump must always be able to generate a higher fuel pressure than the pressure regulated by the pressure regulator.

The injection rate is adjusted by means of the injection time; the injection time is controlled by the DME.

Description of operation: fuel return line

When the engine is at a standstill and the ignition key is in position 0, the fuel return line after the pressure regulator is at zero pressure.

Description of operation: pressure retaining function

The pressure regulator closes when the engine is at a standstill and the ignition key is in position 0. The fuel pressure in the delivery line is retained over an extended period. A non-return valve closes in the fuel pump. These measures help to retain the fuel pressure in the fuel system. Extended starting times are thus avoided.

Complaint: drive characteristic faults, lack of power

1. Run engine at idle speed and measure fuel pressure.

If the measured value is less than the nominal value - 0.2 bar

1. Line cross-sections in fuel feed are constricted or fuel filter is clogged, or
2. Fuel pump voltage supply is not O.K.: e.g. as a result of high contact resistance (corrosion) in plug connection between wiring harness and fuel pump.

If the measured value is greater than the nominal value + 0.2 bar

1. Turn off engine stop and then observe measured value.
2. If measured value drops to nominal value, then line cross-sections in fuel return are constricted or clogged.
3. Check the fuel lines for kinks. If no kinks are visible
4. Replace return lines

If measured value remains too high, then pressure regulator is in all probability faulty.

important

With less likelihood, the return line may be completely blocked. When the pressure regulator is removed, fuel could escape under pressure!

1. Have a cleaning cloth ready and catch and dispose of escaping fuel.
2. Replace the return line but not the pressure regulator.

Complaint: starting problems

1. Run engine briefly at idle speed and switch off.
2. Note down measured value while engine is stopped.
3. Read off measured value again after approx. 20 to 30 minutes while engine is stopped.

Special tool 13 3 010 (hose clamp) is required for the following test.

If the measured value has dropped by more than 0.5 bar

1. Start engine and wait briefly for a stable pressure increase.
2. Switch off the engine and immediately pinch off the delivery line just before the pressure gauge with the special tool 13 3 010.
3. Note down measured value
4. Read off measured value again after approx. 20 to 30 minutes while engine is stopped

If the measured value has now dropped by less than 0.5 bar, the following faults can be present

1. Fault in delivery lines
2. Fault in in-tank delivery hose
3. Faulty pressure-holding non-return valve in fuel pump

Check components. Replace faulty components.

If the measured value has dropped by more than 0.5 bar again

1. Replace pressure regulator

Note. All the fuel hoses and hose clips which were detached within the framework of the checks must be replaced. Interrogate fault memory of DME control unit. Check stored fault messages. Rectify faults. Now clear the fault memory.

13 31 029 Checking fuel pump delivery pressure (M54)

Special tools required

1. 13 3 010
2. 13 5 220
3. 61 3 050

Switch off ignition.

Catch and dispose of escaping fuel.

Remove cover from fuel injectors.

Remove dust cap (1) from measuring valve on fuel rail.

Scheme 1

Prepare special took kit 13 5 220 (consisting of 13 5 221 and 13 5 222).

Scheme 2

Unscrew check valve (1) on special tool kit 13 5 220.

Fit special tool kit 13 5 220 on measuring valve and tighten knurled nut until hand-tight.

Start engine.

Screw in check valve (1) until a pressure reading is indicated on DIS Tester.

Scheme 3

Measuring fuel pressure

1. Connect pressure sensor to DIS Tester
2. Start engine.
3. Select Measurement.
4. Multimeter function appears
5. Select Pressure test
6. Read off fuel pressure

Compare actual value of test pressure with specified value. See FUEL SYSTEM - TECHNICAL DATA .

Switch off engine.

Checking fuel pump

Detach fuel pump relay. See RELAYS .

Note. Check whether fuel pump no longer starts up during engine starting procedure (engine fails to start).

Connect special tool 61 3 050 to terminal (87) and terminal (30).

Press button and read off fuel pump delivery pressure on DIS Tester.

Compare actual value with specified value of delivery pressure.

Scheme 4

Keep special tool 13 3 010 ready for further tests.

Further tests are described in 13 31... Notes On Fuel Pressure Check (Reference Pressure: Environment)

Scheme 5

Note. Interrogate fault memory of DME control unit.

Check stored fault messages.

Rectify faults.

Then clear fault memory.

13 41 500 Replacing idle speed control valve (M52TU, M54)

Necessary preliminary tasks

1. Switch off ignition.
2. Disconnect battery ground wire.
3. See «12 00... INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY»(/bmw/z4/e85e86-2002-2005/remont/gauges-instrument-panels/#engine-electrical-system-repair__12-00-instructions-for-disconnecting-and) .

M52TU only

Remove intake filter housing.

Pull Bowden cable upwards out of holder (1) and suspend from throttle.

Scheme 6

Loosen hose clamps (1).

Detach air intake hose section from throttle assembly and idle actuator.

Scheme 7

Installation

To facilitate installation, fit air-mass flow sensor with intake hose (1). Coat intake hose (1) with antiseize agent.

Scheme 8

M54 E46/E53 only

Remove complete intake hose (between intake filter housing and throttle assembly).

M54 E60/E61/E65/E66 only

Remove intake hose.

M52TU and M54

Unfasten following plug connections

Scheme 9

1. Resonance flap
2. Idle speed control valve

Installation location

Idle actuator (2) is fitted below intake air manifold, directly above throttle (1).

Scheme 10

Release screw (1) on cable duct mounting.

Release screws (2) on holder of idle actuator (3).

Remove idle actuator with holder from intake air manifold.

Scheme 11

Detach idle actuator (2) from rubber retainer (4).

Always replace gasket (1) from idle actuator (2) to intake air manifold. However, during reinstallation, do not fit gasket on idle actuator but install first in intake air manifold.

Scheme 12

Installation

Replace seal (1).

Coat gasket (1) on inside with antiseize agent.

Scheme 13

Note. Interrogate fault memory of DME control unit.

Check stored fault messages.

Rectify faults.

Then clear fault memory.

13 53 240 Replacing complete injection pipe (M54)

Necessary preliminary tasks

1. Switch off ignition.
2. Remove cover for fuel injectors.

Unclip plug connections (1) from holders and disconnect.

When replacing injection pipe

Remove both holders for plug connections (1) from injection pipe.

Disconnect plug connection of intake air temperature sensor (2).

Disconnect plug connection (3) on solenoid valve of VANOS adjustment unit.

Detach terminal strip (4) for fuel injectors from injection pipe.

Recycling

Fuel in fuel lines is under pressure (approx. 3 - 5 bar). Fuel escapes when fuel lines are detached. Catch and dispose of escaping fuel.

Observe country-specific waste-disposal regulations.

Scheme 14

Z3, E85, E39, E46 and E53

Note. For a better overview, this work step is shown on an engine that has been removed.

Unclip fuel line (1) from holder (2).

Follow instructions for unlocking fuel line.

Unlock fuel line (1) from cylinder head at rear.

Scheme 15

Release screws (1) and remove injection pipe with fuel injectors.

Installation

Coat sealing rings of fuel injectors with anti-seize agent to facilitate fitting of injection pipe.

Scheme 16

13 53 540 Replacing, sealing fuel hoses

Recycling

Catch and dispose of escaping fuel.

Observe country-specific waste-disposal regulations.

Version with hose clamps

Release hose clamps.

Remove hoses (1) and (2).

Installation

Scheme 17

1. Fuel hoses and hose clamps must be replaced each time they are removed!

Version with compressed air connection

Blow fuel back into tank with a short blast of compressed air (max. 3 bar) at compressed air connection (1).

Scheme 18

Version, fuel hoses without integrated unlocking facility

Unlock fuel hoses with special tool 16 1 050 and detach hoses.

Installation

Scheme 19

1. Check O-ring in fuel hose and sealing surfaces on fuel lines for damage; replace components if necessary.
2. Coat O-ring for assembly with anti-friction agent.

Fuel hoses with integrated unlocking facility

Press fuel hose (1) downwards and keep pressed.

Scheme 20

Press unlocking ring (2) upwards, keep pressed and detach fuel hose (1).

Installation

Scheme 21

1. Check O-ring in fuel hose and sealing surfaces on fuel lines for damage; replace components if necessary.
2. Coat O-ring for assembly with anti-friction agent.

M43, M44

Cars with screw-mounted fuel feed line (2)

Follow installation instructions (1) and (2).

Installation instruction 1

Scheme 22

1. Always replace fuel hose (1) and hose clamps once they have been removed.

M43, M44

Installation instruction 2

Scheme 23

1. Always replace O-ring. Coat O-ring with anti-friction agent.
2. Clean sealing faces of fuel feed line.
3. If necessary, replace fuel feed line.
4. For Tightening Torque, refer to 13 53 4A in «FUEL SUPPLY SYSTEM - TIGHTENING TORQUES»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-supply-system-tightening-torques) .

Seal off fuel hoses

Fuel hoses with hose clamps

Seal hoses with special tool 13 3 010.

Installation

Scheme 24

1. Fuel hoses and hose clamps must be replaced each time they are removed!

Fuel hoses with quick-release couplings

Seal fuel hoses (1) with special tool 13 5 281.

Seal fuel lines (2) with special tool 13 5 282.

Installation

Scheme 25

1. Check O-ring in fuel hose and sealing surfaces on fuel lines for damage; replace components if necessary.
2. Coat O-ring for assembly with anti-friction agent.

13 54 030 Removing and installing/sealing throttle assembly (M54)

Necessary preliminary tasks

1. Switch off ignition
2. Disconnect battery negative lead from battery and lay to one side Follow «12 00... INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY»(/bmw/z4/e85e86-2002-2005/remont/gauges-instrument-panels/#engine-electrical-system-repair__12-00-instructions-for-disconnecting-and) .
3. If fitted (E85): remove sound generator . See «13 74 001 Removing And Installing/Replacing Sound Generator (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-74-001-removing-and-installingreplacing)
4. Remove air intake hose . See «13 54 250 Replacing Intake Hose (Between Air-Mass Flow Sensor And Connecting Piece) (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-54-250-replacing-intake-hose) or «13 54 251 Replacing Intake Hose (Between Connecting Piece And Throttle Assembly) (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-54-251-replacing-intake-hose) .

Release screws (1) of cable duct mounting.

Place cable channel to one side.

Scheme 26

Unlock plug (1) and detach from throttle assembly (3).

Release screws (2) and remove throttle assembly (3).

Scheme 27

Installation

Replace sealing ring (1) on throttle assembly (2).

Scheme 28

13 54 250 Replacing intake hose (between air-mass flow sensor and connecting piece) (M54)

Necessary preliminary tasks

1. Switch off ignition.
2. Remove top section of air cleaner housing. . See «13 72 001 Replacing Air Cleaner Element (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-72-001-replacing-air-cleaner) .
3. Remove air-mass flow sensor. . See «13 62 560 Removing And Installing/Replacing Airmass Flow Sensor (M54)»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-62-560-removing-and-installingreplacing) .

Loosen hose clamp.

Remove intake hose (1).

Scheme 29

13 54 251 Replacing intake hose (between connecting piece and throttle assembly) (M54)

Necessary preliminary tasks

1. Switch off ignition.
2. Disconnect intake hose.

Release hose clamps (1).

Remove vacuum hose.

Detach intake hose (2) from throttle assembly and idle speed control valve.

Scheme 30

13 62 531 Replacing coolant temperature sensor (M52TU, M54)

Turn off ignition.

Installation location

Coolant temperature sensor (1) is fitted below intake air manifold in cylinder head of cylinder 6.

Remove intake air manifold.

Scheme 31

Disconnect plug connection (1).

Unscrew temperature sensor.

Installation

Tightening torque, see 13 62 2AZ in FUEL SUPPLY SYSTEM - TIGHTENING TORQUES .

Check coolant level, top up coolant if necessary.

Scheme 32

Note. Read out fault memory of DME control unit.

Check stored fault messages.

Rectify faults.

Then clear fault memory.

13 62 560 Removing and installing/replacing airmass flow sensor (M54)

Necessary preliminary tasks

1. Read out fault memory of DME control unit.
2. Switch off ignition.
3. Remove upper intake filter housing section.

Unlock plug (1) and remove.

Loosen hose clamp.

Pull air-mass flow sensor (2) from air intake hose.

Note. Illustrations show E85.

Scheme 33

Installation

Check sealing ring (1) between air-mass flow sensor and intake filter housing for damage, replace if necessary.

Coat sealing ring (1) with suitable antiseize agent.

Note. Illustrations show E85.

Scheme 34

Installation

Arrow on air-mass flow sensor indicates direction of air flow.

Install air-mass flow sensor between intake filter housing and intake hose so that arrow points in direction of intake hose.

Note. Illustrations show E85.

Scheme 35

Unfasten hose clip (1).

Unlock plug (2) and remove.

Pull hot-film air-mass flow sensor (3) off air intake hose.

Installation

Observe throughflow direction (4).

Scheme 36

Check sealing ring (1) for damage and replace if necessary.

Secure sealing ring (1) in upper air filter housing section.

Attach sealing ring (2) to air-mass flow sensor.

Installation

Coat all sealing rings with suitable antiseize agent.

Scheme 37

Installation

Check stored fault messages.

Now clear the fault memory.

13 64 541 Replacing all fuel injectors

Necessary preliminary tasks

1. Switch off ignition
2. Remove «Complete Injection Pipe»(/bmw/z4/e85e86-2002-2005/remont/fuel-system/#fuel-system-repair-instructions__13-53-240-replacing-complete-injection) .

Detach retainer (1).

Detach fuel injector from injection pipe.

Installation

Check sealing rings, replace if necessary.

Insert fuel injector fully into injection pipe then pull out until groove is flush with edge of injection pipe.

Push on retainer.

Scheme 38

Installation

Coat sealing rings of fuel injectors with anti-seize agent to facilitate fitting of injection pipe.

13 71 000 Removing and installing intake filter housing (M54)

Necessary preliminary tasks

1. Switch off ignition.
2. Remove top section of intake filter.

Unfasten screws.

Remove intake filter housing (1).

Scheme 39

Installation

Install guide rail (1) on intake filter housing on rubber mount (2).

Scheme 40

13 74 001 Removing and installing/replacing sound generator (M54)

Loosen hose clamp.

Open quick-release coupling (1) on rear side.

Withdraw sound generator (2) from intake pipe and sound pipe (3) and remove.

Scheme 41

13 72 001 Replacing air cleaner element (M54)

E85 only

Open clips (1).

Open retainers (2) on air-mass flow sensor.

Lift top section (3) of intake filter housing.

Scheme 42

E53, E46 and E85

Remove air cleaner element.

Installation

Clean top and bottom sections of intake filter housing from inside.

Install new air cleaner element.

Check seal between air-mass flow sensor and air cleaner top section for damage, replace if necessary.

Coat seal with antiseize agent to facilitate joining of air cleaner and throttle body.

Scheme 43

13 90 500 Replacing tank vent valve (M54)

Necessary preliminary tasks

1. Check stored fault messages
2. Switch off ignition

Installation location

Tank vent valve is fitted at front on intake air manifold.

Unlock and detach plug connection (1).

Unlock and detach vent hose (2).

Remove hose (3).

Scheme 44

Note. Read out fault memory of DME control unit.

Rectify faults.

Now clear the fault memory.

See also:
• FUEL SYSTEM - TECHNICAL DATA
• RELAYS
• 12 00... INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY
• FUEL SUPPLY SYSTEM - TIGHTENING TORQUES
• 13 31 029 Checking Fuel Pump Delivery Pressure (M54)
• 13 31... Notes On Fuel Pressure Check (Reference Pressure: Environment)
• 13 74 001 Removing And Installing/Replacing Sound Generator (M54)
• 13 54 250 Replacing Intake Hose (Between Air-Mass Flow Sensor And Connecting Piece) (M54)
• 13 54 251 Replacing Intake Hose (Between Connecting Piece And Throttle Assembly) (M54)
• 13 72 001 Replacing Air Cleaner Element (M54)
• 13 62 560 Removing And Installing/Replacing Airmass Flow Sensor (M54)
• Complete Injection Pipe