Principle Of Fuel Injection Operation - BMW 1999-2005 M3 Service Manual

Fuel Injection
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of quality OBD scan tools.
In addition to the BMW
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there are many inexpensive
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programs and handheld units
available. Although these tools
have limited capabilities as
compared to the dedicated tools,
they are powerful diagnostic tools.
These tools read live data
streams, freeze frame information
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For the DIY owner, simple
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available. These inexpensive
BMW-only tools are capable of
checking for DTCs as well as
turning off the illuminated MIL, and
resetting the service indicator
lights.
See 020 Maintenance
specialty tool manufacturer contact
information.
Principle of operation
The DME fuel injection system is
completely electronic in operation.
Intake air, engine coolant temperature,
crank and camshaft positions, engine
speed and many other engine
operating parameters are measured
electronically and the information is
supplied to the engine control module
(ECM).
Based on input information, the ECM
controls the ignition coils, fuel injectors,
for
2/25/2009 9:55 PM