BMW X5: Ignition Management
Most of the ignition system components have remained the same for all NG6 engines for 2007. There are some minor changes to the ignition coils that apply to all versions. The coils have been optimized for more durability.
Spark Plugs
The spark plugs for the N51 and N52KP remain the same as N52. However, the N54 uses a completely new spark plug from Bosch. The spark plug design consists of a 12 mm thread which contrasts from the 14 mm design on the N52 which prevents any possibility of improper installation.
The hex on the spark plug is also a 12 point design which requires a special tool. The tool (socket) has a "thinwall" design to facilitate access in the confined area of the N54 cylinder head.
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Fig. 69: Identifying Spark Plugs
Spark Plug Diagnosis (N54)
Due to the proximity of the spark plug to the fuel injector nozzle, any divergence in the fuel spray may cause possible spark plug damage. This makes spark plug diagnosis an important part of N54 service concerns.
Information gained by the spark plug diagnosis may indicate possible fuel injector faults. Spark plug replacement interval has been reduced to 45,000 miles for the N54.
The Fig. 70 below can be used to assist in diagnosis:
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Fig. 70: Identifying Spark Plug Wear Pattern
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Emissions Management
The N54 and N52KP meet ULEV II requirements for 2007. There are not many
changes to the emission
systems on these engines. The N54 engine has 2 underbody catalysts in addition
to the "near engine" c
Performance Controls
Cooling System
The cooling system of the N54 engine consists of a radiator circuit and an
isolated oil cooling circuit. The fact
that there is an isolated oil-cooling circuit ensures that heat is not
SEE MORE:
Information On Replacing Shock Absorbers
Facts:
When a shock absorber is faulty on one side (leaking, noises, limit values
exceeded on the shock tester), often
both shock absorbers on the axle in question are replaced.
E32, E34, E38, E39 : In the case of rear spring struts with ride-height control,
there is always a slight oil
spillage
Engine Identification
Drive in engine numbers at marked surface with impact tool.
M47 / M47TU / M47T2
Fig. 1: M47 / M47TU / M47T2 Engine Identification
M57 / M57TU / M57T2
Fig. 2: M57 / M57TU / M57T2 Engine Identification
M67 / M67TU
Fig. 3: M67 / M67TU Engine Identification
N47
Fig. 4: N47 Engine Identification
M52
