Parts Catalog Accessories Catalog Tech Info Tech Forums
 
Follow Pelican Parts on Facebook Follow Pelican Parts on Twitter Follow Pelican Parts on Instagram Follow Pelican Parts on YouTube Follow Pelican Parts on Pinterest Follow Pelican Parts on Tumblr
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Engine Management Systems
 
Bookmark and Share

Pelican Technical Article:

Engine Management Systems

Nick Czerula

Time:

1 hours1 hrs

Tab:

$300

Talent:

*****

Tools:

ECM flash tool, supplied with software

Applicable Models:

X3 E83 (2004-06)
X3 E83 facelift (2007-10)

Parts Required:

DME flash tool and software

Hot Tip:

Use this info to better understand your BMW X3 engine

Performance Gain:

Fuel economy and performance

Complementary Modification:

Upgrade DME software

X3 engine management systems--an overview

BMW X3 cars (2004 - 2010) are equipped with digital engine management systems (called Digital Motor Electronics or DME). The engine control module (ECM) in these systems is programmed with software for control of fuel injection, ignition and other functions. BMW DME systems comply with second generation on-board diagnostics (OBD II) standards.

The table below summarizes the engines used in X3 cars:

Years, Models

Engine

2004: 2006

M54 2.5 liter 6-cylinder double-VANOS

M54 3.0 liter 6-cylinder double-VANOS

2007: 2010

N52 3.0 liter 6-cylinder double-VANOS Valvetronic

Engine control module (ECM): The engine control module (ECM or DME) (red arrow) is mounted in the electronics-box (E-box) at the right left (driver side) of the engine compartment.

Fuel supply: An electrically operated fuel pump, located inside the fuel tank, supplies high pressure fuel to the engine fuel rail. Depending on engine application, M54 fuel pressure varies between 3.5 and 5 bar (51 to 73 psi). N52 5 bar (72.5 psi).

Fuel delivery: The ECM meters the fuel output of the injectors using pulse width signals. It varies the pulse width based on input signals. Inputs to the ECM include: air intake volume using mass airflow sensor signal, ambient and coolant temperature signals, accelerator pedal signal, crankshaft and camshaft position signals, knock sensor signals.

Intake system (M54 engine): The resonance / turbulence intake system consists of two sets of three intake runners. Resonance valves are used to vary the length of the runners in order to enhance low end torque at low engine speeds or allow high volume air flow at medium or high engine speeds. The M54 intake is also equipped with a 5.5 mm turbulence port for each cylinder. These ports channel idle and low speed air from the idle speed control regulator to one intake valve in each cylinder. (There are 2 intake valves per cylinder.) Air rushing through one valve causes air swirl and more efficient fuel atomization in the cylinder.

Intake system (N52 engine): The Valvetronic system uses hardware and software to eliminate the conventional throttle mechanism. Instead of a throttle valve, intake air is regulated by adjusting valve lift. The engine is equipped with a Valvetronic actuator motor which operates a cam gear, an eccentric shaft and intermediate levers to vary intake valve lift based on ECM signals. Similarly, the ECM controls idle speed by varying valve actuation. This engine is also equipped with 3-stage variable intake runners in a system known as DISA. DISA valves in the intake manifold are actuated by pulse-width modulated ECM signals.

Variable camshaft timing (VANOS): VANOS is the BMW term for variable camshaft timing. The amount of camshaft timing shift is controlled by the ECM. VANOS uses engine oil pressure to vary intake and exhaust camshaft timing. VANOS provides the following benefits: increased power, higher low end and medium speed torque, improved idle and fuel efficiency, elimination of external EGR plumbing (internal EGR) and quicker warm-up and lower emissions.

Throttle control, idle control: In X3 vehicles the throttle cable is eliminated and throttle actuation is completely electronic (drive-by-wire). In the M54 (6-cylinder) and N52 engines, the idle speed control valve is controlled by the ECM to bypass varying amounts of air around the closed throttle valve.

Ignition and knock control: The ignition system uses one ignition coil per cylinder (mounted under the engine cover), with each coil mounted above a spark plug. Multiple sparks per ignition cycle are used to reduce emissions and extend spark plug life. Spark timing is controlled by the ECM using an ignition spark "map". Spark timing is not adjustable. However, to prevent engine damage in case of adverse conditions or poor fuel quality, knock (detonation) sensors (green arrows) are mounted on the engine crankcase. These are microphones tuned to the frequency of engine knock and communicate such knock to the ECM. The ECM can respond to these signals by changing (usually retarding) ignition timing at one or more cylinders.

Exhaust manifolds and oxygen sensors: Oxygen sensor signals are used by the ECM to control fuel delivery. X3 engines are equipped with two exhaust manifolds, each with an integrated catalytic converter. This allows the converters to heat up a very short time after a cold start. The manifolds are equipped with 4 oxygen sensors, one before each catalyst and one after.

Engine control module (ECM): The engine control module (ECM or DME) (red arrow) is mounted in the electronics-box (E-box) at the left rear (driver side) of the engine compartment.
Figure 1

Engine control module (ECM): The engine control module (ECM or DME) (red arrow) is mounted in the electronics-box (E-box) at the left rear (driver side) of the engine compartment.

Intake system: The X3 engines have six fuel injectors (red arrows) (one per cylinder) actuated electronically.
Figure 2

Intake system: The X3 engines have six fuel injectors (red arrows) (one per cylinder) actuated electronically.

Variable camshaft timing (VANOS): VANOS (red arrow) is the BMW term for variable camshaft timing.
Figure 3

Variable camshaft timing (VANOS): VANOS (red arrow) is the BMW term for variable camshaft timing. The amount of camshaft timing shift is controlled by the ECM. VANOS uses engine oil pressure to vary intake and exhaust camshaft timing. VANOS provides the following benefits: increased power, higher low end and medium speed torque, improved idle and fuel efficiency, elimination of external EGR plumbing (internal EGR) and quicker warm-up and lower emissions.

Ignition and knock control: The ignition system uses one ignition coil per cylinder (mounted under the engine cover (red arrows)), with each coil mounted above a spark plug.
Figure 4

Ignition and knock control: The ignition system uses one ignition coil per cylinder (mounted under the engine cover (red arrows)), with each coil mounted above a spark plug. Multiple sparks per ignition cycle are used to reduce emissions and extend spark plug life. Spark timing is controlled by the ECM using an ignition spark "map". Spark timing is not adjustable. However, to prevent engine damage in case of adverse conditions or poor fuel quality, knock (detonation) sensors (blue arrows point to area under intake) are mounted on the engine crankcase. These are microphones tuned to the frequency of engine knock and communicate such knock to the ECM. The ECM can respond to these signals by changing (usually retarding) ignition timing at one or more cylinders.

Exhaust manifolds and oxygen sensors: Oxygen sensor signals are used by the ECM to control fuel delivery.
Figure 5

Exhaust manifolds and oxygen sensors: Oxygen sensor signals are used by the ECM to control fuel delivery. X3 engines are equipped with two exhaust manifolds, each with an integrated catalytic converter. This allows the converters to heat up a very short time after a cold start. The manifolds are equipped with 4 oxygen sensors, one before each catalyst and one after. The pre-catalyst sensors (B1S1, B2S1) are located in the exhaust manifold on the right side of the engine, just out of view, red arrow points to the tip of B1S1 and B2S1. Post-catalyst sensors on located at the right rear of the engine just after the catalysts.

NG6 New Generation N52 engine: N52 engines change the underhood look quite a bit.
Figure 6

NG6 New Generation N52 engine: N52 engines change the underhood look quite a bit. With a new style intake air housing (blue arrow), updated engine cover (red arrow) and more compact intake manifold (green arrow). Repair procedures for this engine are different from the M54 due to the construction and redesign of the BMW 6-cylinder platform.




Bookmark and Share

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Privacy Statement]
 [Contact Us] [About Us] [Shipping] [Map to our Location] [Careers]

Copyright © Pelican Parts Inc.

Page last updated: Fri 12/9/2016 03:07:22 AM