Original BMW
Spark Plugs
Overview
Located in the cylinder head, spark plugs
transfer the ignition spark to the compressed
fuel-air mixture in the cylinder, providing the
engine with the deciding impulse. When
assembled, each spark plug consists of a
center electrode, a ceramic isolator, a steel
jacket and multiple ground electrodes.
When transferring the ignition spark to the
compressed fuel-air mixture in the cylinder,
the ignition system conducts a high voltage
pulse to the electrodes. Then, at 5–30 kV,
there is a voltage flashover in the form of a
spark between the center electrode and
one of the ground electrodes. Through the
arrangement of the electrodes and the
isolator on Original BMW Spark Plugs,
the ignition spark conducts insulator
deposits from the insulator tip to the ground
electrode. This means that deposits are
carried away with every firing and a reliable
ignition of the fuel-air mixture is ensured
under all conditions. The mixture is then
ignited and the combustion pressure drives
the piston downwards, which is known as
the “working stroke.”
Spark plugs must endure wear-inducing
load changes in stop-and-go traffic as
well as the high-sooting involved with cold
starts. And for highway driving, they need to
withstand voltage discharges from 20–30 kV
approximately 55 times per second.
Main Advantages
– Multiple ground electrodes
for reliable ignition
– Fivefold barrier against
creeping current
– Ninety-five percent
aluminum oxide isolates
for superior reliability
– Excellent cold starting, idling
and acceleration behavior
– Steel housing treated
against corrosion
– Lower pollutant emission
Quality assurance
To guarantee that Original BMW Spark
Plugs can accurately support the optimal
performance and reliable functioning of the
engine, they are subject to BMW ’s stringent
quality requirements.
Cooperation with spark plug specialists
The advanced technology of Original BMW
Spark Plugs is the result of a close, cooperative development process with spark plug
specialists. Currently, BMW offers the best
available technology: “sliding” spark plugs
with multiple ground electrodes and platinum
center electrodes.
Decades of knowledge
Because BMW makes no compromises
when releasing its sparkplugs, it relies on
decades of tried and proven knowledge in
the performance of complex tests and
development regimens. As a result, Original
BMW spark plugs are optimally suited to
vehicle performance characteristics.
Matched to computer-controlled
engine management systems
As a pioneer in digital motor electronics,
BMW guarantees precise igniting through
innovative computer-controlled motor
management systems.
– Semi-slide spark technology
with self-cleaning behavior
– Optimal ignition reliability
for protection of engine
and catalytic converter
– Heat range precisely matched
to BMW engine electronics
– Reliable performance, even
under extreme conditions
Original BMW Spark Plugs | BMW of North America | VT-A-3, June 2006
Features >
Original BMW
Spark Plugs
FEATURes and benefits in depth
Multiple ground electrodes
for reliable ignition
Spark erosion occurs when molecules from the electrode material are gradually stripped away
with every ignition. Over the long term, this leads to material erosion, as the gap between the
electrodes get larger — in extreme cases, it may even cause misfiring. The innovative design of
Original BMW Spark Plugs efficiently counteracts the erosion process through multiple ground
electrodes that extend operating life and ensure reliable ignition. Additionally, these ground
electrodes align the electrical field more precisely and allow the spark to be delivered in the
exact location that will achieve optimal ignition of the fuel-air mixture in the cylinder.
Corrosion-resistant housing
Made from special, surface-treated steel, the housing of Original BMW Spark Plugs prevents
corrosion and seizing of the threads even after a long operating life, while protecting the
cylinder head from damage.
Fivefold barrier against
creeping current
Caused by moisture or contamination, creeping current is unwanted voltage over the
outer insulator that can lead to misfiring and the detrimental effects associated with it.
The insulator of an Original BMW Spark Plug has five ring-shaped barriers with a special
profile that effectively prevents creeping currents and creates a spark in the combustion
chamber between the electrodes.
One hundred percent
reliability
The insulator of an Original BMW Spark Plug is made of 95% aluminum oxide, a material
Excellent cold starting,
idling and acceleration
behavior through semi-slide
spark technology
The innovative semi-slide spark technology of Original BMW Spark Plugs prevents deposits
and malfunctions, providing excellent cold-starting performance, smoother running at idle and
superior acceleration behavior.
Precise heat range
While a spark plug must reach a free-burning temperature of approximately 400 ºC as quickly
as possible for optimal cold-starting behavior, it cannot become too hot for highway driving
(more than 850 ºC), or ignitions will occur on the plug’s glowing components. An optimal heat
range is achieved through the copper core in the center electrode and strict adherence to
component tolerances.
able to withstand extreme mechanical, thermal and chemical conditions. Combustion
pressure up to 40 Bar, vibrations, temperatures up to approximately 850 ºC, and a multitude
of chemical additives in the fuel or oil create an aggressive environment that only high-grade
insulator materials can handle.
Original BMW Spark Plugs | BMW of North America | VT-A-3, June 2006
BMW Advantages