2002 BMW X5 Camshaft

Initial Print Date: 02/2000Revision Date: 6/2000
Subject Page
M54 Engine
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Mechanical changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Performance Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Siemen’s MS 43.0 System
• Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
• I - P - O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
MS 43.0 New functions
• Electronic throttle Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
• Accelerator Pedal Sensor (PWG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
• Electronic Throttle Valve (EDK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
• Main Relay Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
• Engine Optimized Ignition Key OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
• Diagnosis Module Tank Leakage (DM-TL) . . . . . . . . . . . . . . . . . . . . . . .17
• DM-TL Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
• DM-TL Test Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Carry Over Functions
Inputs
• Oxygen Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
• Camshaft Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
• Crankshaft Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
• Misfire Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
• OBD Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
• Mass Air Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Outputs
• VANOS Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
• Electric Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
• Secondary Air Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
• Engine Speed Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
• RZV Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
• Resonance - Turbulence Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
• Idle Speed control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
• Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
• Purge Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Table of Contents

M54 ENGINE
Mechanical Changes
In addition to the increased displacement of the M54B30 engine, several mechanical
changes were incorporated into the engine for reduced emissions and increased fuel econ-
omy. These changes include:
• NEW PISTONS - The piston has a shorter skirt compared to the M52 TU and continues
with the graphite coating for friction and emission reducing measures. The piston rings have
been modified to reduce friction.
• CRANKSHAFT - The crankshaft for the 3 liter M54 is adopted from the S52B32 - M3
engine.
• CAMSHAFT - The camshaft for the 3 liter M54 is modified with more lift (9.7 mm) and
new valve springs to accommodate the increased lift.
• INTAKE MANIFOLD - The intake manifold is modified with shorter ram tubes (20mm
shorter on 3 liter. The diameter of the tubes is increased slightly.
• INJECTION VALVES - The diameter of the injection pintle has increased slightly for the
increased displacement of the 3 liter engine.
4
M54engMS43/ST036/6/2000
ART-0198U29
ART-INJECTOR

26
M54engMS43/ST036/6/2000
CAMSHAFT SENSOR
-INTAKE AND EXHAUST CAMSHAFTS
The "static" Hall sensors are used so that the camshaft positions are recognized once igni-
tion is “on” - even before the engine is started.
The function of the intake cam sensor:
• Cylinder bank detection for preliminary injection
• Synchronization
• Engine speed sensor (if crankshaft speed sensor fails)
• Position control of the intake cam (VANOS)
The exhaust cam sensor is used for position control of the exhaust cam (VANOS)
If these sensors fail there are no substitute values, the system will operate in the failsafe
mode with no VANOS adjustment. The engine will still operate, but torque reduction will be
noticeable.
NOTE: Use caution on repairs as not to bend the impulse wheels
KL 15 KL 15
MS42.0
SOLENOID
OIL TEMP.
SENSOR TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY VENT VENT
SOLENOID
SENSOR SENSOR
MS42
ECM
EXHAUST
INTAKE
MS42.0
ECM
MS 43.0
MS 43.0
MS 43.0

32
M54engMS43/ST036/6/2000
MS 43 CARRY OVER FUNCTIONS
OUTPUT FUNCTIONS -VANOS CONTROL
With the double VANOS system, the valve timing is changed on both the intake and the
exhaust camshafts.
Double VANOS provides the following benefits:
• Torque increase in the low to mid (1500 - 2000 RPM) range without power loss in the
upper RPM range.
• Less incomplete combustion when idling due to less camshaft overlap (also improves
idle speed characteristics).
• Internal exhaust gas recirculation (EGR) in the part load range (reduces NOx and post-
combustion of residual gasses in the exhaust)
• Rapid catalyst warm up and lower “raw” emissions after cold start.
• Reduction in fuel consumption
Double VANOS consists of the following parts:
• Intake and exhaust camshafts with helical gear insert
• Sprockets with adjustable gears
• VANOS actuators for each camshaft
• 2 three-way solenoid switching valves
• 2 impulse wheels for detecting camshaft position
• 2 camshaft position sensors (Hall effect)
The “initial” timing is set by gear positioning (refer to the Repair Instructions for details) and
the chain tensioner. As with the previous VANOS, the hydraulically controlled actuators
move the helical geared cups to regulate camshaft timing. The angled teeth of the helical
gears cause the pushing
movement of the helical cup to be converted into a rotational
movement. This rotational movement is added to the turning of the camshafts and cause
the camshafts to “advance” or “retard”. The adjustment rate is dependent oil temperature,
oil pressure, and engine RPM.

33
M54engMS43/ST036/6/20000
NOTE: With extremely hot oil temperatures Vanos is deactivated (Power loss). If the oil is
too thick (wrong viscosity) a fault could be set.
When the engine is started, the camshafts are in the “failsafe” position (deactivated). The
intake camshaft is in the RETARDED position - held by oil pressure from the sprung open
solenoid. The exhaust camshaft is in the ADVANCED position - held by a preload spring in
the actuator and oil pressure from the sprung open solenoid.
After 50 RPM (2-5 seconds) from engine start, the ECM is monitoring the exact camshaft
position.
The ECM positions the camshafts based on engine RPM and the throttle position signal.
From that point the camshaft timing will be varied based on intake air and coolant temper-
atures.
The double VANOS system is “fully variable”. When the ECM detects the camshafts are in
the optimum positions, the solenoids are modulated (approximately 100-220 Hz) maintain-
ing oil pressure on both sides of the actuators to hold the camshaft timing.
CAUTION:
The VANOS MUST
be removed and installed exactly as described in the Repair
Instructions!
NOTE: If the VANOS camshaft system goes to the failsafe mode (deactivated) there will be
a noticeable loss of power. This will be like driving with retarded ignition or starting from a
stop in third gear.
KL 15 KL 15
MS42.0
SOLENOID
OIL TEMP.
SENSOR TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY VENT VENT
SOLENOID
SENSOR SENSOR
MS42
ECMEXHAUST
INTAKE
MS42.0
ECM
MS 43.0
MS 43.0
MS 43.0

35
M54engMS43/ST036/6/20000
The dual VANOS in conjunction with the variable intake manifold provides an additional
emission control feature.
Because of the improved combustion, the camshaft timing is adjusted for more overlap.
The increased overlap supports internal exhaust gas recirculation (EGR) which reduces
tailpipe emissions and lowers fuel consumption.
During the part load engine range, the intake camshaft overlap opens the intake valve. This
allows limited exhaust gas reflow the intake manifold.
The “internal” EGR reduces the cylinder temperature thus lowering NOx. This feature pro-
vides EGR without the external hardware as seen on previous systems.
INLET
TURBULENCE
IDLE AIR
CONTROL VALVEMDK
INT. EGR
CATALYST
CLOSE TO
ENGINESECONDARY
AIR
INJECTION
(AIR FILTER)OUTLET-VANOS
(228/80-105)INLET-VANOS
(228/80-120)