Fuel Injector: Service and Repair

13 53 310 Removing And Installing/Replacing An Injector (N63)

Special tools required:







WARNING:
Observe warning on cylinder head cover.
Clamp off negative battery terminal (risk of fire due to short-circuiting on dismantling).
Electric fuel pump starts up automatically when door is opened.
Carry out installation work on fuel system only with coolant temperature below 40 °C.







WARNING:
Wear full face guard and protective gloves.
Fuel can emerge spontaneously at high velocity from the fuel injectors.
To reduce the fuel pressure, place rag over fuel injector and carefully tap against the fuel injector with a spanner.
There is a risk of injury if the fuel pressure is not reduced.







IMPORTANT:
Wear safety goggles.
Oil and dirt particles may get into your eyes.

Before removing the injectors, clean or vacuum off injector slots.







IMPORTANT:
Observe without fail the tightening sequences and Tightening torques when reassembling.
Disregard of these requirements may result in leaks.
Adhere to conditions of absolute cleanliness when working on the high-pressure fuel system.
Introduced contaminants can cause malfunctions in the system.
- Do not allow any dirt particles or foreign bodies to get into the system.
- Remove all traces of dirt contamination before removing lines or separate components.
- Use only fluff-free cloths.
- Seal all fuel system openings with protective caps or plugs.
- High pressure lines may be re-screwed a maximum of 10 times.
Injectors are not waterproof.
Carry out engine cleaning/washing only with ignition coil cover fitted.







Necessary preliminary tasks:
- Remove ignition coil of corresponding cylinder

NOTE:
- Ignition coils must not be fouled by fuel.
The resistance of the silicone material is reduced significantly by contact with fuel, which may cause the ignition coil to fail. It is therefore essential to protect the spark plug slot against ingress of fuel with a cloth.

- Before installing ignition coils, clean spark plug slots with compressed air.
- Make sure the spark plug slot is absolutely clean.
- Remove pressure lines on corresponding injectors







NOTE: The following description applies to all injectors.

Release bolt (1) and remove holding-down element (2).







Remove injector (1).

NOTE:
If several injectors are removed, ensure that each injector is reinstalled in its original location (cylinder).
Mark injectors.







After removing, fit protective caps (1 and 3) to injector tip and fuel line connection.
Protective caps are available from BMW Parts Service.







Installation note:
When installing a new injector:
- Use a new uncoupling element (2).
- Remove protective cap (1) from injector tip max. 10 min. before installation (PTFE sealing ring swells up).







Installation note:
When reusing fuel injector:
- Replace decoupling element (2).
- Replace PTFE sealing ring (1).
A PTFE seal which has been heated once by engine operation must be replaced before the fuel injector is reinstalled.







Renew the PTFE sealing ring:
Before replacing PTFE sealing ring (1), make sure hands and work surface are clean and free of oil.
Avoid mechanical contact with injector tip (2).







Remove PTFE sealing ring (1) with special tool 13 0 191 from injector (2).
Use a fluff-free cloth only to remove combustion residues from cylindrical part of injector tip (do not use ultrasound or other tools/agents).
Do not clean injector tip.







Slide new PTFE sealing ring (1) onto mounting taper 13 0 195.







User fingers and mounting taper 13 0 195 to slide PTFE sealing ring (1) onto injector (2).

NOTE:
- Do not use fingernails to slide PTFE sealing ring on.
- Do not use any lubricating agents.
- The sealing ring is expanded when slid on.







To bring the expanded PTFE sealing ring to its installation dimension, slide three assembly sleeves with decreasing diameters onto the injector.
Slide assembly sleeve (1) with large opening first onto injector (1).
Do not use any lubricating agents.







First slide assembly sleeve 13 0 192 (large diameter) onto injector (1).
Then slide assembly sleeve 13 0 193 (medium diameter) onto injector (1).







Finally, press injector (1) into assembly sleeve 13 0 194 (small diameter).

Installation note:
Install injector within 10 minutes or slide on protective cap (Fig. 13 14 05) (PTFE sealing ring swells up).







Installing injector:
Installation of injector is described separately from removal.







Before installing injector in engines that have been run:
- Check injector bore for dirt.
Clean only dirty injector bores.

IMPORTANT: do not damage injector.

- Clean injector bore: To do so, preferably slide injector without uncoupling element (2) but with new PTFE sealing ring (1) in and out of injector bores several times.
The PTFE sealing ring must then be replaced.

- Clean contact surfaces of uncoupling elements (2) in cylinder head.
- Replace decoupling element (2).







IMPORTANT: Injection quantity compensation.

An injector quantity compensation must be carried out if an injector is replaced or changed on the cylinder side.
Injector quantity compensation is carried out with the aid of a so-called adjustment value.
The adjustment value is printed in two blocks of three digits on the injector.
The adjustment value must be read off before installation.







Enter the adjustment value according to the installation location (cylinder) of the injector.
If injector quantity compensation is not carried out, the engine may run roughly or fail to start.
Description of injector quantity compensation at end of instructions.







Installing injector:
Install injector (1).
Install hold-down device (2).

NOTE: Make sure hold-down device (2) is correctly seated.

IMPORTANT: Tighten bolt (3) hand-tight only so that hold-down device (2) is slack and if necessary injector (1) can still be turned.







Install pressure line (2). Tighten nuts (1) manually only.

IMPORTANT:
Connect pressure line (2) without tension only.
To ensure distortion-free installation of the pressure line and to avoid damaging the thread, it must be possible for both nuts to be screwed on easily by hand.
If the nuts cannot be screwed on easily by hand, the injector must if necessary be turned a little.







Turn injector (1) if necessary in direction of arrow until nuts on pressure line can be easily screwed on by hand.
Tighten nut (2) of pressure line hand-tight.
Then tighten down bolt for hold-down device (3).
Tightening torque 13 53 5AZ.







Adhere to tightening sequence:
- First tighten down pressure line on injector.

Tighten down nut on injector with special tool (1) 13 0 161 and to torque (2). In so doing, grip hexagon head of injector with wrench (3).
Tightening torque 13 53 2AZ.







For cylinders 4 and 8, tighten pressure line (1) with torque (2) and crowfoot wrench (3). In so doing, grip hexagon head of injector with spanner.
Tightening torque 13 53 2AZ.







- After this, tighten pressure line on rail.

Tighten down pressure line on rail with torque wrench (1) and special tools (2) 00 1 440, (3) 13 0 162 and (4) 13 0 161.
Tightening torque 13 53 2AZ.







Perform an injection quantity compensation:
- Connect BMW diagnosis system
- Identify vehicle
- Select "Function selection"
- Select "Service functions"
- Select "Engine electronics"
- Select "Adjustment function"
- Select "Adjust injectors"
- Change "Test schedule"
- For each replaced injector, the adjustment value must be entered according to the installation location (cylinder).







Assemble engine.
Bleed fuel system with BMW diagnosis system.
Check fuel system for tightness.
Check function of DME.