Fuel System - Repair (n62) BMW X5 E70

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.

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.

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 (N62TU2)

Special tools required

1. 13 5 220
2. 61 3 050

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. Remove «ACOUSTIC COVER»(/bmw/x5/e70-2006-2010/remont/mechanical/#engine-repair-n62__removing-acoustic-cover-n62n62tu) and air filter housing on right
4. Remove right ignition coil cover

Remove dust cap on measuring valve of fuel rail.

Unscrew non-return valve (1) on special tool kit 13 5 220 .

Mount special tool kit 13 5 220 on fuel rail and tighten knurled nut until hand-tight.

Start engine.

Screw in non-return valve (1) until a pressure reading is indicated on the DIS Tester.

Scheme 89

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 Test Pressure: 13 53 INJECTORS AND LINES, FUEL PRESSURE REGULATOR N62 / N45 / N46 Test pressure / nominal value bar ± 0.2 3.5 Switch off engine. Assemble vehicle and check fuel system for leaks.

Checking fuel pump

Remove fuel pump relay.

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

Operate button and read off fuel pump delivery pressure at DIS Tester.

Scheme 90

Notes on FUEL PRESSURE CHECK .

Installation

Now clear the fault memory.

Replacing fuel filter (M57T2, N52K, N57, N62TU)

Necessary preliminary tasks

1. Switch off ignition.
2. Remove rear underbody protection. See «51 47 491 REMOVING AND INSTALLING/REPLACING REAR UNDERBODY PROTECTION»(/bmw/x5/e70-2006-2010/remont/door-locks-anti-theft-systems/#body-equipment-repair__51-47-491-removing-and-installingreplacing) .
3. Remove rear left underbody panelling. See «51 47 ... REMOVING AND INSTALLING/REPLACING LEFT OR RIGHT UNDERBODY PANELLING»(/bmw/x5/e70-2006-2010/remont/door-locks-anti-theft-systems/#body-equipment-repair__51-47-removing-and-installingreplacing) .

Recycling

Catch and dispose of escaping fuel.

Observe country-specific waste-disposal regulations.

Release screws (1).

Vehicles without fuel preheating only

Release clamps on front and back fuel lines on fuel filter. Disconnect front and back fuel lines from fuel filter. Close fuel lines with suitable plugs from set of special tools 32 1 270! Remove fuel filter.

Scheme 91

13 53 240 Replacing complete fuel rail (N62TU)

Special tools required

1. 13 5 281

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. Remove «intake filter housing»(/bmw/x5/e70-2006-2010/remont/fuel-system/#fuel-system-repair-n62__13-71-000-removing-and-installingreplacing) .
4. Remove «intake hose»(/bmw/x5/e70-2006-2010/remont/fuel-system/#fuel-system-repair-n62__13-54-250-replacing-intake-hose) .

Release screws and remove holder (1). Remove ignition coil covers (2).

Scheme 92

Unlock and disconnect following plug connections.

1. Fuel rail, left and right, on cable duct.
2. Pulse generator on left exhaust and inlet camshafts.
3. Left eccentric shaft sensor.
4. Tank venting valve.
5. Alternator.
6. Throttle-valve assembly.
7. All solenoid valves.
8. Both temperature sensors.
9. Oil-pressure switch.
10. Air conditioner compressor.

Remove vent line (1). Disconnect plug connections (2) of knock sensors from cable ducts (4). Unlock plugs on servomotors (3) and disconnect. Lay cable ducts (4) to one side.

Scheme 93

Remove protective cap (1) from compressed air connection. Blow fuel back into tank with a short blast of compressed air (max. 3 bar) at compressed air connection (1). Release screws. Remove both fuel rails (2) towards top.

Scheme 94

Recycling Fuel escapes when fuel line is detached. Catch and dispose of escaping fuel. Observe country-specific waste-disposal regulations.

Unlock and disconnect fuel hose (1).

Scheme 95

Seal fuel hose with special tool 13 5 281.

Scheme 96

Release screws. Unlock connector and remove.

Scheme 97

Lever out retainers (1). Pull fuel injectors out of fuel rails.

Scheme 98

Installation: Replace sealing rings on fuel injectors and coat with anti-friction agent.

Note. Observe routing of suppression lines. Now clear the fault memory.

13 54 030 Removing and installing/sealing throttle valve assembly (N62, N62TU)

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. Remove «intake hose»(/bmw/x5/e70-2006-2010/remont/fuel-system/#fuel-system-repair-n62__13-54-250-replacing-intake-hose) .

Unlock plug (1) and remove. Release screws. Remove throttle assembly (2).

Scheme 99

Installation: Replace sealing ring (1) of throttle assembly (2).

Scheme 100

13 54 250 Replacing intake hose (between air-mass flow sensor and throttle valve assembly)

Necessary preliminary tasks

1. Switch off ignition

Unclip cover (1) and remove.

Scheme 101

Removing right intake duct

Note. Illustration shows and text refers to the left intake duct. The procedure is identical for the right intake duct.

Lever out expansion rivets (1). Press lock (2) and raise intake duct (3). Detach intake duct (3) from air filter housing and remove.

Scheme 102

Unfasten hose clips. Detach intake hose (1) from air-mass flow sensor and from throttle valve assembly.

Scheme 103

13 62 560 Removing and installing/replacing air-mass flow sensor (N62TU)

Necessary preliminary tasks

1. Read out fault memory of DME control unit; if necessary, work through test schedules.
2. Switch off ignition.
3. Remove «intake hose»(/bmw/x5/e70-2006-2010/remont/fuel-system/#fuel-system-repair-n62__13-54-250-replacing-intake-hose) .

Unlock plug (1) and remove. Release screws. Remove air-mass flow sensor (2).

Scheme 104

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

13 62 010 Removing and installing/replacing differential pressure sensor (N62TU)

Necessary preliminary tasks

1. Read out fault memory of DME control unit; if necessary, work through test schedules.
2. Switch off ignition.
3. Remove intake air manifold.

Note. Installation location: On rear side of intake air manifold.

Release screws. Tightening torque, see 13 62 1AZ in 13 62 SENDERS FOR CONTROL UNIT (N62TU) . Pull differential pressure sensor (1) out of intake air manifold.

Scheme 105

13 62 531 Replacing coolant temperature sensor (N62, N62TU)

Necessary preliminary tasks

1. Read out fault memory of DME control unit; if necessary, work through test schedules.
2. Switch off ignition.
3. Remove intake air manifold.

Coolant temperature sensor is mounted on water pipe at front. Unlock plug (1) and remove. Release temperature sensor (2).

Scheme 106

Installation: Tightening torque, see 13 62 2AZ in 13 62 SENDERS FOR CONTROL UNIT (N62TU) . Vent cooling system and check for leaks. If necessary, top up coolant.

13 64 541 Replacing all fuel injectors

Note. This work step is described in removing complete injection pipe .

13 71 000 Removing and installing/replacing intake filter housing (N62TU)

Necessary preliminary tasks

1. Switch off ignition.

Unclip cover (1) and remove.

Scheme 107

Removing left and right intake ducts: Lever out expansion rivets (1). Press lock (2) and raise intake duct (3). Detach intake duct (3) from air filter housing and remove.

Scheme 108

Note. Illustration shows and text refers to the left intake duct. The procedure is identical for the right intake duct.

Unlock plug (1) and remove. Release clamp (2) and detach air intake hose. Detach intake ducts from intake filter housing (3). Detach intake filter housing (3) from rubber mount and remove.

Scheme 109

13 72 002 Replacing both air cleaner elements (N62TU)

Necessary preliminary tasks

1. Switch off ignition.

Unclip cover (1) and remove.

Scheme 110

Unlock plug (1) and remove. Release clamp (2) and detach air intake hose. Open retainers and remove upper section (3) of intake filter housing.

Scheme 111

Remove air cleaner elements (1).

Scheme 112

Installation: Clean upper and lower sections of intake filter housing from inside. Insert new air cleaner elements.

13 90 500 Replacing tank vent valve (N62, N62TU)

Necessary preliminary tasks

1. Read out fault memory of DME control unit; if necessary, work through test schedules.
2. Switch off ignition.
3. Remove engine acoustic cover.

E70 only: Lever out expansion rivets (1). Press lock (2) and raise intake duct (3). Detach intake duct (3) from air filter housing and remove.

Scheme 113

Installation location: Tank venting valve is fitted at front on left side of cylinder head cover. Unlock vent hose on intake air manifold and disconnect. Unlock vent hose on tank venting valve (2) and disconnect. Unlock plug (1) and remove. Remove tank venting valve (2) from holder.

Scheme 114

See also:
• ACOUSTIC COVER
• 51 47 491 REMOVING AND INSTALLING/REPLACING REAR UNDERBODY PROTECTION
• 51 47 ... REMOVING AND INSTALLING/REPLACING LEFT OR RIGHT UNDERBODY PANELLING
• 13 62 SENDERS FOR CONTROL UNIT (N62TU)
• FUEL PRESSURE CHECK
• intake filter housing
• intake hose
• removing complete injection pipe