1992 BMW 318i Connecting rod
[x] Cancel search: Connecting rodPage 8 of 759
Please
read
these
warnings
and
cautions
before
proceeding
with
maintenance
and
repair
work
.
CAUTION-
"
See
also
Warnings
onpage
vi¡
"
Beforedoing
any
electrical
welding
on
cars
equipped
with
ABS,
disconnect
the
battery
negative
(-)
terminal
(ground
strap)
and
the
"
If
you
lack
the
skills,
tools
and
equipment,
ora
suitable
work-
ABS
control
unit
connector
.
shop
for
any
procedure
described
in
this
manual,
we
suggest
you
leave
such
repairs
to
an
authorized
BMW
dealer
or
other
qualified
"
On
cars
equipped
with
anti-theft
radios,
make
sureyou
know
the
shop
.
correct
radio
activation
code
before
disconnecting
the
battery
or
removing
the
radio
.
lf
the
wrong
code
is
entered
into
the
radio
"
BMW
is
constantly
improving
its
cars
and
sometimes
these
when
power
is
restored,
that
radio
may
lock
up
and
be
renderedchanges,
both
in
parts
and
specifications,
are
made
applicable
to
inoperable,
even
if
the
correct
code
is
thenentered
.
earlier
models
.
Therefore,
part
numbers
listed
in
this
manual
are
for
reference
only
.
Always
check
with
your
authorized
BMW
dealer
"
Always
make
sure
ignition
is
off
before
disconnecting
battery
.
parts
department
for
the
latest
information
.
"
Label
battery
cablesbefore
disconnecting
.
Onsome
models,
"
Before
starting
a
job,
make
certain
that
you
have
all
the
neces-
battery
cablesarenot
color
coded
.
sary
tools
and
parts
on
hand
.
Read
al¡
the
instructions
thoroughly,
do
not
attempt
shortcuts
.
Use
tools
appropriate
to
the
work
and
"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
con-
use
only
replacement
parts
meeting
BMW
specifications
.
Make-
trol
module
memory
Using
special
BMW
diagnostíc
equipment,
shift
tools,
parts
and
procedures
will
not
make
good
repairs
.
check
forfault
codes
prior
to
disconnecting
the
battery
cables
.If
the
Check
Engine
light
is
illuminated,
see100
Engine-General
for
"
Use
pneumatic
and
electric
tools
only
to
loosenthreaded
parts
On-Board
Diagnostics
(OBD)
fault
code
information
.
lf
any
other
and
fasteners
.
Never
use
these
tools
to
tighten
fasteners,
espe-
system
faults
have
been
detected
(indicated
by
an
ílluminated
cially
on
light
alloy
parts
.
Always
use
a
torque
wrench
to
tighten
warning
light),
see
an
authorized
BMW
dealer
.
fasteners
to
the
tightening
torque
specification
listed
.
"
If
a
normal
or
rapid
charger
is
used
to
charge
battery,
the
battery
"Be
mindful
of
the
environment
and
ecology
.
Before
you
drain
the
mustbe
disconnected
and
removed
fromthe
vehicle
in
order
to
crankcase,
find
outthe
proper
way
to
dispose
of
the
oil
.
Do
not
avoid
damaging
paint
and
upholstery
pour
oil
onto
the
ground,
down
a
drain,
or
into
a
stream,
pond
orlake
.
Dispose
of
in
accordance
withFederal,
State
and
Local
laws
.
"Do
not
quick-chargethe
battery
(for
boost
starting)
for
longer
than
one
minute
.
Wait
at
least
one
minute
before
boosting
the
bat-
e
If
battery
power
is
lost
or
the
battery
has
been
disconnected,
the
tery
a
second
time
.
powerwindows
must
be
re-initialized
.
Both
one
touch
up/down
and
pinch-protection
will
be
inactive
until
windows
are
re-initial-
"
Connect
and
disconnect
a
battery
charger
only
with
the
battery
ized
.
See
512
Door
Windows
.
charger
switched
off
.
"
The
control
module
for
the
anti-lock
brake
system
(ABS)
cannot
withstand
temperatures
from
a
paint-drying
booth
or
aheat
lamp
in
excess
of
203°F
(95°C)
and
should
not
be
subjected
to
temper-
atures
in
excess
of
185°F
(85°C)
for
more
than
twohours
.
"
Sealed
or
"maintenance
free"
batteries
shouldbeslow-charged
only,
at
anamperage
ratethat
is
approximately
10%
of
the
bat-
tery's
ampere-hour
(Ah)
rating
.
"
Do
not
allow
battery
chargingvoltage
to
exceed
16
.5
volts
.
If
the
battery
begins
producing
gas
or
boiling
violently,
reduce
the
charg-
ing
rate
.
Boosting
a
sulfated
battery
at
a
high
charging
rate
can
cause
an
explosion
.
Page 12 of 759
010-
4
FUNDAMENTALS
FOR
THE
DO-ITYOURSELF
OWNER
Fig
.
3
.
BMW
supplied
jack
correctly
positioned
in
front
jacking
point
.
Most
of
the
repairs
and
maintenance
tasks
described
in
this
manual
can
be
successfully
completedby
anyone
with
basic
tools
and
abilities
.
To
prevent
getting
in
too
deep,
know
what
WARNING-
the
wholejob
requires
before
starting
.
Read
the
procedure
thor-
"
Do
not
rely
on
thetransmission
or
the
emergen-
oughly,
from
beginning
to
end,
in
order
to
know
just
what
to
ex
cybrake
to
keep
thecar
from
rolling
.
They
are
pect
and
what
parts
will
have
to
be
replaced
.
nota
substitute
for
positively
blocking
the
oppo-
site
wheel
.
"
Never
work
undera
car
that
is
supported
only
by
ajack
Use
jack
stands
that
are
properly
de-
signed
to
support
the
car
.
See
Tools
.
Working
under
car
safely
1
.
Disconnect
negative
(-)
cable
from
battery
so
that
no
one
else
can
start
thecar
.
Let
others
know
what
you
will
be
doing
.
CAUTION-
Prior
to
disconnecting
the
battery
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
vüi
.
2
.
Raisecar
slowly
as
described
above
.
3
.
Use
at
least
two
jack
stands
to
support
thecar
.
A
jack
is
atemporary
lifting
device
and
should
not
be
used
alone
to
support
the
car
while
you
are
under
it
.
Use
jack
stands
designed
for
the
purpose
of
supporting
a
car
.
For
more
information
on
jack
stands,
see
Toolsbelow
.
WARNING
-
Do
notusewood,
concrete
blocks,
orbricks
to
sup-
port
acar
.
Woodmay
split
.
Blocks
or
bricks,
while
strong,
are
not
designed
for
that
kind
of
load,
and
may
brakkor
collapse
.
ADVICE
FOR
THE
BEGINNER
4
.
Place
jack
stands
on
firm,
solid
surface
.
If
necessary,
use
a
flat
board
or
similar
solid
object
to
provide
a
firm
footing
.
5
.
Lower
car
slowly
until
its
weight
is
fully
supportedby
jack
stands
.
Watch
to
make
sure
that
the
jack
stands
do
not
tip
orlean
as
thecar
settles
on
them
.
6
.
Observe
all
jacking
precautions
again
when
raising
car
to
remove
jack
stands
.
ADVICE
FORTHE
BEGINNER
The
tips
in
the
paragraphs
that
follow
are
general
advice
to
help
any
do-it-yourself
BMW
owner
perform
repairs
and
main-
tenance
tasks
more
easily
and
more
professionally
.
Planning
Ahead
Cleanliness
Keeping
things
organized,
neat,
and
clean
is
essential
to
do-
ing
a
good
job
.
When
working
under
the
hood,
fender
covers
will
protect
the
finish
from
scratches
and
other
damage
.
Make
sure
the
car
is
relatively
clean
so
thatdi
rt
under
the
cover
does
not
scratch
the
finish
.
Any
repair
job
will
be
less
troublesome
if
the
parts
are
clean
.
For
cleaning
old
parts,
there
are
many
solvents
and
parts
cleaners
commercially
available
.
For
cleaning
parts
priorto
assembly,
commercially
available
aerosol
cans
of
parts
cleaner
or
brake
cleaner
are
handy
to
use,
and
the
cleaner
will
evaporate
completely
.
WARNING
-
Virtually
all
solvents
used
for
cleaning
parts
are
highly
flammable,
especially
in
aerosol
form
.
Use
wíth
extreme
care
.
Do
not
smoke
.
Do
not
use
these
products
near
any
source
of
heat,
sparksor
flame
.
Let
any
solvent
orcleaning
product
dry
completely
.
Low-
pressure,
dry
compressed
air
is
helpful
if
available
.
Also,
use
only
lint-free
rags
for
cleaning
and
drying
.
Page 43 of 759
GENERAL
.
.....
.
.
.
.
.
.
.
...
.
.
.
.
.
.
.
.
.
...
100-1
Cylinder
Block
and
Crankshaft
.
.
.
.
.
.
.
.
.
...
100-1
Connecting
Rods
and
Pistons
.
.
.
.
.
.
.
.
.
.
.
.
.
100-1
Cylinder
Head
and
Valvetrain
.
.
.
.
.
.
.
.
.
.
.
.
.
100-2
VANOS
(Variable
Valve
Timing)
.
.
.
.
.
.
.
.
...
100-2
DISA
(Dual
Resonance
Intake
System)
.
.
.
.
.
100-3
Engine
Management
System
.
.
.
.
.
.
.
.
.
.
.
.
.
100-3
Ignition
......
.
.
.
.........
.
.
.
.
.
.
.
.
.
.
.
.
100-5
Fuel
Delivery
..
.
.
.
.....
.
...
.
.
.
.
.
.
.
.
.
.
.
.
100-5
Cooling
System
.
...........
.
.
.
.
.
.....
.
.
100-5
Lubrication
System
.........
.
.
.
.
.
.
.
.
.
.
.
.
100-5
MECHANICALTROUBLESHOOTING
.
.
.
.
100-5
Warnings
and
Cautions
..
.
...
.
.
.
.
.
.
.
.
.
.
.
.
100-5
Cylinder
compression,
checking
.
.
.
.
.
.
.
.
.
.
.
100-6
EngineMechanical
Troubleshooting
Table
.
.
.
100-7
DRIVEABILITY
TROUBLESHOOTING
...
100-8
GENERAL
There
are
various
engíne
configurations
used
in
the
1992-
1998
E36
cars
.
See
Table
a
.
On
both
four-
and
6-cylinder
engines,
the
cylinder
block
is
cast
¡ron
with
integral
cyiinders
.
The
cyiinders
are
exposed
on
all
sides
to
circulating
coolant
.
The
fully
counterweighted
crankshaft
rotates
in
replaceable
split-shell
main
bearings
.
Oiiways
drilled
into
the
crankshaft
pro-
vide
bearing
lubrication
.
O¡I
seals
pressed
into
alloy
sea¡
hous-
ings
are
installedat
both
ends
of
the
crankshaft
.
100
Engine-General
Tablea
.
Engine
Specifications
ENGINE-GENERAL
100-1
On-Board
Diagnostics
(OBD)
...
.
.
.
.
.
.
.
.
.
.
.
100-8
Basic
Requirements
....
.
.
.
...
.
.
.
.
.
....
.100-11
Preventive
Maintenance
......
.
.
.
.
.
.....
100-11
Basic
Engine
Settings
..
.
.....
.
.
.
.
.
.....
100-11
Oxygen
Sensors
.
.
.
...
.
.
.
...
.
.
.
.
.
....
.100-11
Air
Flow
Measurement
and
Vacuum
Leaks
.
.100-12
Battery
Voltage
.
.
...........
.
.
.
.
.
.....
100-12
Wiring
and
Harness
Connections
.
.
.
.
.....
100-13
Ground
Connections
...
.
.....
.
.
.
.
.
.....
100-13
Fue¡
Supply
....
.
...........
.
.
..
.....
.100-14
TABLES
a
.
Engine
Specifications
...
...
...........
.
..
..
.100-1
b
.
Engine
Management
Systems
..
..
...........
..
100-5
c
.
Engine
Mechanical
Troubleshooting
..........
.
.
100-8
d
.
OBD
1
Fault
(Blink)
Codes
(1992-1995
models
only)
.
...
..
..
..........
..
.100-9
e
.
Engine
Driveability
Troubleshooting
...........
.100-15
Model
Engine
code
No
.
of
Dispiacement
Compression
Horsepower
cyiinders
liters
(cu
.
in
.)
ratio
SAE
net
@
rpm
318i/is/¡C
1992-1995
M42
4
1
.8
(109
.6)
10
.0
:1
100
@
6000
1996-1998
M44
4
1
.9
(115
.6)
~
10
.0
:1
103
@
6000
323ís/iC
1998
M52
6
2
.5
(152
.2)
10
.5
:1
168
@
5,500
325i/is/iC
1992-1995
M50
6
2
.5
(152
.2)
10
.0
:1
110
@
5,900
328i/is/iC
1996-1998
M52
6
2
.8
(170
.4)
10
.2
:1
190
@
5,300
M3
1995
S50US
6
3
.0
(182
.5)
10
.5:1
240
@
6,000
1996-1998
S52US
6
3
.2
(192
.3)
10
.5:1
240
@
6,000
Cylinder
Block
and
Crankshaft
Connecting
Rods
and
Pistons
The
forged
connecting
rods
use
replaceable
split-shell
bearings
at
the
crankshaft
endand
solid
bushings
at
the
pis-
ton
pin
end
.
The
pistonsare
of
the
three-ring
typewith
two
up-
per
compression
rings
and
a
lowerone-piece
o¡i
scraper
ring
.
Fui¡-floating
piston
pins
are
retained
with
circlips
.
GENERAL
Page 47 of 759
ignition
Table
b
.
Engine
Management
Systems
engine
has
high
mileage
.
Engine
1
System
4-cylinder
engines
M42
(1992-1995)
Bosch
DME
Ml
.7
M44
(1996-1998)
Bosch
DME
M5
.2
(OBD
II)
6-cylinder
engines
M50
(1992)
Bosch
DME
M3
.1
M50
VANOS
(1993-1995)
Bosch
DME
M3
.3
.1
M52
(1996-1998)
Siemens
MS41
.1
(OBD
II)
S50US
(1995)
Bosch
DME
M3
.3
.1
S52US
(1996-1998)
Siemens
MS41
.1
(OBD
II)
Both
the
4-cylinder
and
6-cylinder
engines
use
a
distributor-
less
ignition
system
with
individual
ignition
coils
for
each
cylin-
der
.
FuelDelivery
Pressurized
fuel
from
the
in-tank
fuel
pump
is
injected
via
solenoid-type
fuel
injectors
.
The
ECM
controls
the
opening
and
closing
of
the
injectors
by
switchingthe
ground
side
of
each
injector
circuit
.
The
exact
amount
of
fuel
injected
is
de-
termined
by
the
amount
of
timethe
injectors
are
open
.
Cooling
System
Whenever
the
engine
is
running,
acoolant
pump
circulates
coolant
through
the
engine
and,
if
either
heater
control
valves
are
open,
through
the
heater
core
in
the
passenger
compart-
ment
.
The
coolant
absorbs
excess
heat
and
carries
it
to
the
ra-
diator
where
it
is
transferred
into
the
passing
airstream
.
A
thermostat
controls
the
flow
of
coolant
through
the
radiator
based
on
engine
temperature
.
Lubrication
System
The
lubrication
system
is
pressurized
whenever
theengine
is
running
.
The
oil
pump
draws
oil
through
a
pickup
in
the
bot-
tom
of
the
oil
pan,thenforces
it
through
a
replaceable
oil
filter
and
finto
the
engine
oíi
passages
.
On
4-cylinder
engines,
the
oil
pump
is
mounted
to
the
front
engine
cover
.
On
6-cylinder
engines,thechain-driven
oil
pump
is
bolted
to
the
bottom
of
the
cylinder
block
.
A
pressure
relief
valve
limits
the
maximum
system
pres-
sure
.
A
bypass
valve
prevents
the
oil
filter
from
bursting
and
insures
engine
lubrication
should
the
filter
become
plugged
.
See
119
Lubrication
System
for
additional
information
.
ENGINE-GENERAL
100-
5
Various
versions
of
DME
systems
are
usedon
thecars
cov-
MECHANICAL
TROUBLESHOOTING
ered
by
this
manual
.
See
Table
b
.
Each
system
is
highly
adaptive
to
compensate
for
things
suchasengine
wear
and
When
troubleshooting
an
engine
that
fails
to
start
or
runs
vacuum
leaks
.
poorly,
first
check
its
mechanical
condition-particularly
if
the
Warnings
and
Cautions
For
personal
safety,
as
well
asthe
protection
of
sensitive
electronic
components,
the
following
warnings
and
cautions
must
be
adhered
to
during
all
troubleshooting,
maintenance,
and
repairwork
.
WARNING
-
"
The
ignition
system
produces
high
voltages
that
can
be
fatal
.
Avoid
contact
with
exposed
termi-
nals
anduse
extreme
caution
when
working
on
a
car
with
the
ignition
switched
on
or
the
engine
running
.
"
Do
not
touch
or
disconnect
any
high
voltage
ca-
bles
from
the
coil,
distributor,
orspark
plugs
while
the
engine
is
running
or
being
cranked
by
the
starter
"
Connect
and
disconnect
the
engine
manage-
ment
system
wiring
and
test
equipment
leads
only
when
the
ignition
is
switched
off
.
"
Gasoline
is
highly
flammable
and
its
vapors
are
explosive
.
Do
not
smoke
or
work
on
a
car
near
heaters
or
other
fire
hazards
when
diagnosing
and
repairing
fuel
system
problems
.
Have
a
fire
extínguisher
available
in
case
of
an
emergency
.
"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
control
module
memory
.
Using
special
BMW
diagnosnnc
equipment,
check
for
fault
codes
prior
to
disconnecting
the
battery
cables
.
If
the
Check
Engine
lightis
illuminated,
see
On-
Board
Diagnostics
(OBD)
forfault
code
infor-
mation
.
If
any
other
system
faults
havebeen
de-tected
(indicated
byan
illuminated
warning
light),
see
an
authorized
BMW
dealer
.
CAUTION-
"
Prior
to
disconnecting
the
battery,
read
the
bat-
tery
disconnection
cautions
gíven
at
the
front
of
this
manual
on
page
viii
.
"
Do
notconnect
any
test
equipment
that
delivers
a
12-volt
power
supply
to
terminal15
(+)
of
the
ignition
coil
.
The
current
flow
may
damage
the
ECM
.
In
general,
connect
test
equipment
only
as
specified
by
BMW,
this
manual,
or
the
equip-
ment
maker
.
"
Do
not
disconnect
the
battery
with
the
engine
running
.
Do
notrunthe
engine
with
any
of
the
sparkplug
wires
disconnected
.
MECHANICAL
TROUBLESHOOTING
Page 55 of 759
If
a
battery
cableconnection
hasno
visible
faults,
but
is
still
suspect,
measure
the
voltage
drop
across
the
connection
.
A
large
drop
indicates
excessive
resistance,
meaning
the
con-
nection
is
corroded,
dirty,
or
damaged
.
Clean
or
repair
the
connection
and
retest
.
NOTE-
For
instructions
on
conducting
a
voltage
drop
test,
and
other
general
electrical
troubleshooting
information,
see600
Electrical
System-General
.
Wiring
and
Harness
Connections
The
electronic
fuel
injection
and
ignition
systems
operate
at
low
voltage
and
current
values,
making
them
sensitive
to
small
increases
in
resistance
.
The
electrical
system
is
routine-
ly
subjected
to
corrosion,
vibration
and
wear,
so
faults
or
cor-
rosion
in
the
wiring
harness
and
connectors
are
common
causes
of
driveability
problems
.
Visually
inspect
all
wiring,
connectors,
switches
and
fuses
in
the
system
.
Loose
or
damaged
connectors
can
cause
inter-
mittent
problems,
especially
the
smallterminals
in
the
ECM
connectors
.
Disconnect
the
wiring
harness
connectors
to
check
for
corrosion
;
and
use
electrical
cleaning
spray
to
re-
move
contaminants
.
Often,
simply
disconnecting
and
recon-
necting
a
dirty
connector
several
times
will
clean
the
terminals
and
help
to
reestablish
good
electrical
contact
.
If
a
wiring
harnessconnectorhasno
visible
faults,
but
is
still
suspect,
measure
the
voltage
drop
across
the
connector
.
A
large
drop
indicates
excessive
resistance,
meaning
the
con-
nector
is
corroded,
dirty
or
damaged
.
Clean
or
repair
the
con-
nector
and
retest
.
Ground
Connections
For
any
electrical
circuit
to
work,
it
must
make
acomplete
path,
beginning
at
the
positive
(+)
battery
terminal
and
ending
at
the
negative
(-)
terminal
.
The
negative
(-)
battery
cable
is
attached
to
the
car's
chassis
.
Therefore,
any
wireor
metal
part
attached
to
the
chassis
provides
a
good
ground
path
back
to
the
negative
(-)
battery
terminal
.
Poorground
connections
are
amajor
source
of
driveabílity
problems
.
If
any
of
themainground
connections
for
the
igni-
tion
system
or
the
fuelinjection
system
are
faulty,
the
in-
creased
resistance
in
that
circuit
will
cause
problems
.
Visually
inspect
al¡
ground
wires
and
connections
for
breaks,
looseness
or
corrosion
.
Be
careful
because
wires
sometimes
break
internally
or
in
areas
not
easily
visible
.
The
main
grounds
for
the
DME
system
are
shown
in
Fig
.
11,Fig
.
12,
and
Fig
.
13
.
Also
check
the
main
fuel
pump
ground
in
the
center
console,
below
the
emergency
brake
handle
.
If
a
ground
connection
has
no
visiblefaults,
but
is
still
suspect,
measure
the
voltage
drop
acrossthe
connection
.
A
large
drop
indicates
high
resistance,
meaning
the
connection
is
corroded,
dirty
or
damaged
.
Clean
or
repair
the
connection
and
retest
.
ENGINE-GENERAL
100-
1
3
UU,~uyi
Fig
.
11
.
Mainground
(arrow)
for
engine
management
system
.
Grounds
are
in
right
rear
of
engine
compartment
.
Fig
.
12
.
Mainground
for
ignition
coils
on
MS
41
.1
engine
manage-
ment
system
(arrow)
.
DRIVEABILITY
TROLIBLESHOOTING
Page 138 of 759
121-2
BATTERY,
STARTER,
ALTERNATOR
CHARGING
SYSTEM
TROUBLESHOOTING
Static
currentdraw,
checking
Charging
system
diagnostics
requires
special
test
equip-
ment
.
If
the
test
equipment
is
not
available,
charging
system
fault
diagnosis
can
be
performedby
an
authorized
BMW
deal-
eror
other
qualified
repair
shop
.
A
general
troubleshooting
guide
is
given
in
Table
a
.
Charging
System
Quick-Check
As
a
quick-check,
use
a
digital
multimeter
lo
measure
volt-
2
.
Disconnect
battery
negative
(-)
cable
.
age
across
the
battery
terminals
with
the
key
off
and
then
again
with
the
engine
running
.
The
battery
voltage
should
be
CAUTION-
about12
.6
volts
with
key
off
and
approximately
14
.0
volts
with
Prior
to
disconnecting
the
battery,
read
the
battery
the
engine
running
.
If
the
voltage
does
not
increase
when
the
disconnection
cautions
given
at
the
front
of
this
engine
is
running,there
is
a
fault
in
the
charging
system
.
manual
onpaga
viii
.
NOTE
-
The
regulated
voltage
(engine
running)
should
be
be-
tween
13
.5
and
14
.5,
depending
on
temperatura
and
operating
conditions
.
If
the
voltage
is
higher
than
14
.8,
the
voltage
regulator
is
most
Mely
faulty
.
Check
for
clean
and
tight
battery
cables
.
Check
the
ground
cable
running
from
the
negative
(-)
battery
terminal
lo
the
chassis
and
the
ground
cable
running
from
the
engine
lo
the
chassis
.
Check
the
alternator
drive
belt
condition
and
tension
.
If
the
battery
discharges
over
time,
there
may
be
a
constant
drain
or
current
draw
on
the
battery
.
A
small
static
drain
on
the
battery
is
normal,
but
a
largedrain
will
cause
the
battery
lo
quickly
discharge
.
Make
a
static
current
draw
test
asthe
first
step
when
experiencing
battery
discharge
.
1
.
Make
sure
ignition
and
al¡
electrical
accessories
are
switched
off
.
3
.
Connect
a
digital
ammeter
between
negative
battery
post
and
negative
battery
cable
lo
measure
current
.
See
Fig
.
1
.
Wait
at
least
one
minuta
lo
get
an
accurate
reading
.
A
range
of
about
0
lo
100
milliamps
is
normal,
dependingon
the
number
of
accessories
that
need
constant
power
.
A
current
of
400
milliamps
(0.4
amp)
or
more
may
indicate
a
problem
.
Table
a
.
Battery,
Starter
and
Charging
System
Troubleshooting
Symptom
1
Probable
Cause
1
Correctiva
Action
1
.
Engine
cranks
slowlyor
not
a
.
Battery
cables
loose,
dirty
orcor-
a
.
Clean
or
replace
cables
.
See020
Maintenance
Program
.
a
tall,
solenoíd
clicks
when
roded
.
starter
is
operated
.
b
.
Battery
discharged
.
b
.
Charge
battery,
test
and
replace
if
necessary
.
c
.
Body
ground
straploose,
dirty
or
c
.
Inspect
ground
strap,
clean,
tighten
or
replace
if
necessary
.
corroded
.
d
.
Poor
connection
at
starter
motor
d
.
Check
connections,
test
for
voltage
at
starter
.
Test
for
voltage
at
terminal
30
.
neutral
safety
or
clutch
interlock
switch
.
e
.
Starter
motor
or
solenoid
faulty
.
e
.
Test
starter
.
2
.
Battery
will
not
stay
a
.
Short
circuit
draining
the
battery
.
a
.
Test
for
excessive
current
drainwith
everything
electrical
in
the
charged
more
than
a
few
vehicle
off
.
days
.
b
.
Short
driving
trips
and
high
elec-
b
.
Evaluate
driving
style
.
Where
possible,
reduce
electrical
con
trical
drain
on
charging
system
sumption
when
making
short
trips
.
does
not
allow
battery
to
re-
charge
.
c
.
Drive
belt(s)
worn
or
damaged
.
c
.
Inspect
or
replace
multi-ribbed
belt(s)
.
See
020
Maintenance
Program
.
d
.
Battery
faulty
.
d
.
Test
battery
and
replace
íf
necessary
.
e
.
Battery
cables
loose,
dirty
orcor-
e
.
Clean
or
replace
cables
.
See
020
Maintenance
Program
.
rodad
.
f
.
Alternatoror
voltage
regulator
f
.
Test
alternator
and
voltage
regulator
.
faulty
.
3
.
Battery
losing
water
.
1
a
.
Battery
overcharging
.
1
a
.
Test
voltage
regulator
for
proper
operation
.
4
.
Lights
dim,
light
intensity
a
.
Drive
belt(s)
worn
or
damaged
.
a
.
Inspect
or
replace
multi-ribbed
belt(s)
.
See
020
Maintenance
varies
with
engine
speed
.
Program
.
b
.
Alternatoror
voltage
regulator
b
.
Test
alternator
and
voltage
regulator
.
faulty
.
c
.
Body
ground
straps
loose,
dirty
or
c
.
Inspect
ground
straps,
clean,
tighten
or
replace
as
necessary
.
corroded
.
CHARGING
SYSTEM
TROUBLESHOOTING
Page 152 of 759
130-
6
FUEL
INJECTION
Warnings
and
Cautions
For
personal
safety,
as
well
as
the
protection
of
sensitive
electronic
components,
the
following
warnings
and
cautions
should
be
adhered
to
when
working
on
the
engine
manage-
ment
system
.
GENERAL
WARNING
-
"
The
ignition
system
produces
high
voltages
that
can
be
fatal
.
Avoid
contact
with
exposed
termi-
nals
.
Use
extreme
caution
when
working
onacar
with
the
ignition
switched
on
or
the
engine
run-
ning
.
"
Do
not
touch
or
disconnect
any
high
voltage
ca-
bles
from
the
coils
or
spark
plugs
while
the
engine
is
running
or
beingcranked
by
the
starter
.
"
Connect
and
disconnect
the
DME
system
wiring
and
test
equipment
leads
only
when
the
ignition
is
switched
off
.
"
Gasoline
is
highly
flammable
and
fts
vaporsare
explosive
.
Do
not
smoke
or
work
on
a
car
near
heaters
or
other
fire
hazards
when
diagnosing
and
repalring
fuel
system
problems
.
Have
a
tire
extinguisher
avaílable
in
case
of
an
emergency
.
"
When
working
onan
open
fuel
system,
wear
suit-
able
hand
protection,
asprolonged
contact
wfth
fuel
can
cause
illnesses
and
skin
disorders
.
"
Renew
fuel
system
hoses,
clamps
and
O-rings
any
timethey
are
removed
.
"
Before
makingany
electrical
tests
that
require
the
engine
to
be
cranked
using
the
starter,
disable
the
ignition
system
as
described
in
120
Ignition
System
.
CAUTION-
"
Prior
to
disconnecting
the
battery,
read
the
bat-
tery
disconnectinn
cautions
given
at
the
front
of
this
manual
onpage
vifi
.
"
Do
not
connect
any
test
equipment
that
delivers
a
12-volt
power
supply
to
terminal
15
(+)
of
the
ig-
nitioncoil
.
The
current
flow
may
damage
the
ECM
.
In
general,
connect
test
equipment
only
as
speclfied
by
BMW,
this
manual,
or
the
equipment
maker
.
"
Only
use
a
digital
multlmeter
for
electrical
test
.
"
Only
use
an
LED
test
light
for
quick
tests
.
"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
memory
.
Check
for
fault
codes
prior
to
disconnecting
the
battery
cables
.
ff
the
Check
Engine
light
ís
illuminated,
see100En-
gine-General
for
DME
fault
code
information
.
ff
any
other
system
faults
have
been
detected
(indi-
catedbyan
illuminated
warning
light),
see
an
au-
thorized
BMW
dealer
.
Additional
systems
with
self-diagnostic
capabilities
include,
ABS
(Anti-
lock
brakes),
SRS
(Airbags),
EML
and
ASC+T
and
AST
(Traction
Control)
.
"
Do
not
run
the
engine
wfth
any
of
the
spark
plug
wires
dlsconnected
.
Catalytic
converter
damage
may
result
.
"
Always
waitat
least
40
seconds
afterturning
off
the
ignition
before
removing
the
engine
control
module
(ECM)
connector
.
ff
the
connector
isre-
moved
before
this
time,
residual
power
in
the
sys-
tem
relay
may
damage
the
control
module
.
"
Cleanliness
is
essential
when
working
onan
open
fuel
system
.
Thoroughly
clean
fuel
line
con-
nections
and
surroundlng
areas
before
loosen-
ing
.
Avoid
moving
the
car
.
Only
fnstall
cleanparts
.
"
Fuel
system
cleaners
and
other
chemical
addi-
tives
other
than
those
specifically
recommended
by
BMW
may
damage
the
catalytic
converter,
the
oxygensensor
or
other
fuel
supply
components
.
Page 155 of 759
Oxygen
Sensor
FUEL
DELIVERY
TESTS
FUEL
INJECTION
130-
9
"
Voltage
at
¡dle
..
.
..
..
....
0
.2
to
0
.8
VDC,
fluctuating
Checking
fuel
delivery
is
afundamental
part
of
trouble-
shooting
and
diagnosing
the
engine
management
system
.
Fuel
pressure
directly
influences
fuel
delivery
.
An
accurate
NOTE-
fuel
pressure
gauge
will
be
needed
to
make
the
tests
.
To
check
sensorresponse
to
lean
and
rich
mixtures,
createenairleak,
orpull
vacuumhoseofffue¡
pressure
There
are
three
significant
fuel
delivery
values
to
be
mea-
regulator
to
increase
fuel
pressure
.
sured
:
3
.
Separate
sensorharness
connector
from
sensor
.
Check
for
battery
voltage
between
terminals
3
and
4
(green
wire
and
brown
wire)
in
main
wiring
harness
side
of
con-
nector
with
engine
running
.
If
voltage
is
not
present,
check
oxygen
sensor
heater
relay
.
See610
Electrical
Component
Locations
.
4
.
Check
heater
element
resistance
between
terminals
3
and
4
in
sensor
side
of
connector
.
If
element
is
electri-
cally
open
(no
continuity),
replace
sensor
.
NOTE-
The
oxygen
sensor
heater
relay
is
mounted
in
the
main
power
distributfon
box
in
the
left
rear
of
the
engine
com-
partment
.
Refer
to
Fig
.
6
.
The
heater
relay
is
energized
wíth
positive
(+)
battery
voltage
from
the
main
relayanda
switched
ground
from
the
ECM
.
See
Electrical
Wir-
ing
Diagrams
.
"
Oxygen
sensor
to
exhaust
pipe
...
..
55
Nm
(41
ft-Ib)
"
System
pressure-created
by
the
fuel
pump
and
main-
tained
by
the
pressure
regulator
.
"
Fuel
delivery
volume-created
by
the
fuel
pump
and
af-
fected
by
restrictions,
suchasclogged
fuel
filter
.
"
Residual
pressure-the
pressure
maintained
in
the
closed
system
after
the
engine
and
fuel
pump
are
shut
off
.
Procedures
for
measuring
the
first
two
quantities
arede-
scribed
in
160
Fuel
Tank
and
Fuel
Pump
.
Residual
fuel
pres-
sure
is
checked
using
the
procedure
detailed
later
in
this
group
.
Operating
fuel
pump
fortests
To
operate
the
fuel
pump
for
testing
purposes
without
hav-
íng
to
runthe
engine,
the
fuel
pump
relay
can
be
bypassed
to
power
the
pump
directly
.
Fuel
pump
relay
location
is
shown
in
Fig
.
6
.
5
.
¡f
oxygen
sensor
doesn't
produce
a
fluctuating
voltage
To
runthe
fuel
pump,
remove
the
fuel
pump
relay
and
con-
and
preheater
circuit
is
OK,
replace
sensor
.
nect
the
socket
for
relayterminal
30
to
the
socket
for
relay
ter-
mina¡
87
with
a
fused
jumper
wire
.
After
completing
the
tests,
NOTE-
remove
the
jumper
wire
.
If
not
already
applied,
coat
the
oxygen
sensor
threads
with
an
anti-seize
compound
before
installation
.
Do
not
CAUTION-
getthe
compound
on
the
sensor
tip
.
"
Relay
locations
may
vary
.
Use
care
when
identi-
fying
relays
and
making
electrical
checks
at
the
fuselrelay
panel
.
See
610
Electrical
Compo
Tightening
Torque
nent
Locations
for
additional
relay
information
.
"
The
fuel
pump
relay
has
a
1
.5
mm2
red
wire
at
ter-
minal
30
in
the
relay
socket
.
Terminal
87
has
a
1
.5
mm
2
greenlviolet
wire
.
See
Electrical
Wiring
Di-
agrams
for
additional
wiring
information
.
NOTE-
Thejumper
wire
should
be
1.5
mm2
(14
ga
.)
and
in-
clude
an
in-line
tuse
holder
with
a15
amp
tuse
.
To
avoid
fuselrelay
panel
damage
from
repeated
connect-
ing
and
disconnecting,
also
include
a
toggle
switch
.
A
heavy-duty
jumper,
BMW
tool
no
.
61
3
050,
is
also
available
from
an
authorized
BMW
dealer
.
FUEL
DELIVERYTESTS