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
100-8
ENGINE-GENERAL
Symptom
1
Probable
cause
and
correctiveaction
1
.
Engine
will
not
start
or
run
.
Starter
cranks
a
.
No
fuel
reaching
engine
.
Check
forfuelin
tank
.
engine
at
normal
speed
.
Fuel
pump
notoperating
.
Repair
Group
160
b
.
No
spark
.
Check
ignition
system
.
Repair
Group
120
c
.
Incorrect
valve
timing
.
Check
timing
chain
.
Repair
Group
117
2
.
Check
Engine
warning
light
illuminated
.
a
.
DME
engine
management
system
self-diagnostic
fault
detected
.
Sea
an
authorized
BMW
dealer
or
other
qualified
shop
for
OBD
II
fault
code
diagnosis
.
See
also
On-
board
Diagnostics(OBD),
given
later
inthis
repair
group
.
3
.
White
exhaust
smoke
(steam)
.
a
.
Failed
cylinder
head
gasket
(probably
accompanied
bylowcompression
readings)
.
Replace
gasket
and
resurface
cylinder
head
if
necessary
.
Repair
Group
113
4
.
Blue-gray
exhaust
smoke
and
oily
spark
a
.
Contaminated
or
gasoline-diluted
engine
oil
.
Change
engine
oil
and
replace
oil
filter
.
plugs
.
Indicates
oii
burning
in
combustion
.
Repair
Group
020
b
.
Faulty
valve
guide
seals
or
valve
guides
.
Replace
valve
guide
oil
seals
or
overhaul
cylinder
head
.
Repair
Group
116
5
.
Pinging
or
rattling
when
under
load,
a
.
Ignition
timing
too
advanced
.
Ignition
knocksensors
faulty
(CheckEngine
light
traveling
uphill,
or
accelerating,
especially
illuminated)
.
Repair
Group
120fromlow
speeds
.
Indicates
pre-ignition
or
b
.
Fuel
octane
leve¡
toolow
.
detonation
.
c
.
Engine
running
too
hot
or
overheating
.
Check
cooling
system
.
Repair
Group
170
6
.
Light
metallic
tapping
that
varies
directly
with
engine
speed
.
Oil
pressure
warning
light
not
illuminated
.
7
.
Light
metallic
knock
that
varies
directly
with
enginespeed
.
Oil
pressure
warning
light
blinking
or
fully
illuminated
;
may
be
most
noticeable
during
hard
stops
or
cornering
.
8
.
Screeching
or
squealing
under
load
that
a
.
Loose,worn,
or
damaged
drive
belt
.
Inspect
belt(s)
.
Repair
Group
020
goesaway
when
coasting
.
9
.
Growling
or
rumbling
that
varieswith
engine
a
.
Remove
drive
belt(s)toidentifyfaulty
component
.
Check
for
play,
bearing
roughness,
rpm
.
Indicates
abad
bearing
or
bushing
in
and
loose
mountings
.
Refer
to
appropriate
repair
group
for
repair
procedures
.
an
engine-driven
accessory
.
DRIVEABILITY
TROUBLESHOOTING
On-Board
Diagnostics
(OBD)
On-Board
Diagnostics
is
incorporated
into
al¡
engine
man-
Two
generations
of
OBD
are
usedon
thecars
covered
by
agement
systems
used
on
the
cars
covered
by
this
manual
.
this
manual
:
Therefore,
checking
for
fault
codes
should
be
the
first
step
in
troubleshootinga
driveability
problem
.
For
additional
informa-
On-Board
Diagnostics
tion
on
engine
management
and
repair
see130
Fuel
Injec-
tion
.
"
1992-1995models
....
.
..
....
.
..
.......
OBD
I
"
1996-1998models
.
....
..
.
.
.
..
.
........
OBD
II
DRIVEABILITY
TROUBLESHOOTING
Tablec
.
Engine
Mechanical
Troubleshooting
b
.
Warped
or
cracked
cylinder
head
.
Resurface
or
replace
cylinder
head
.
Repair
Group
113
c
.
Cracked
cylinder
block
.
Replace
engine
or
short
block
.
c
.
Worn
piston
rings
.
Overhaul
or
replace
engine
.
d
.
Failed
cylinder
head
gasket
.
Replace
gasket
.
Repair
Group
113
d
.
Air/fuel
mixture
too
lean
(Check
Engine
light
illuminated)
.
Repair
Group
130
a
.
Valveclearances
excessive
.
Check
hydraulic
valve
adjusters
.
Repair
Group
116
b
.
Low
oil
pressure
orpossibly
defective
warning
light
circuit
.
Check
oil
pressure
andwarning
light
circuit
.
Repair
Group
119
c
.
Dirty
oil
.
Change
oil
.
Repair
Group
020
.
a
.
Low
oil
leve¡
.
Check
and
correct
oil
leve¡
.
b
.
Low
oil
pressure/worn
or
faulty
oil
pump
.
Oil
pump
pickup
restricted/clogged
.
Check
oil
pressure
.
Repair
Group
119
The
OBD
system
detects
emissions-related
engine
manage-
ment
malfunctions
and
tucos
on
the
Check
Engíne
lightin
the
in-
strument
cluster
.
TheCheck
Engine
light
will
stay
on
until
the
code(s)are
called
up
and
the
memory
is
erased
.
When
faulty
are
detected,
the
OBD
system
stores
a
Diagnostic
Trouble
Code
(DTC)
in
the
system
ECM
.
In
addition,
the
Check
Engine
warn-
ing
light
will
come
on
if
an
emissions-related
fault
is
detected
.
Graphic
representation
of
flashing
Check
Engine
light
fault
code
:
1221
-
;
5
Seconds
.
~-
2
.5;-
Fault
code
and
meaning
Corrective
action
Code
1286
:
Knock
control
test
pulse
(DME
3
.3
.1
only)
Check
DME
control
module
inputs/outputs
.
Control
module
may
be
faulty
Repair
Group
130
Code
1000
(light
remains
off)
:
End
of
fault
code
output-all
fault
codes
have
been
displayed
.
No
~
corrective
action
necessary
.
Repeat
test
if
necessary
Code
1444
:
No
more
faults
.
No
corrective
action
necessary
.
This
code
must
be
present
lo
erase
fault
memory
Basic
Requirements
Preventive
Maintenance
The
following
list
contains
basic
checks
that
should
be
made
when
experiencing
driveability
problems
.
1
.
Check
intake
(induction)
system
for
leaks
.
Check
for
cracked,
loose,
or
disconnected
hoses
and
duct
work
.
Check
that
all
hose
clamps
are
tight
.
NOTE-
An
air
leak
allows
unmeasured
airto
enter
the
engine,
offen
resulting
in
an
in
overly
lean
fuel
mixture
and
causing
driveability
problems
which
will
cause
the
Check
Engine
light
to
come
on
.
Table
d
.
OBD
I
Fault
(Blink)
Codes
(continued)
(1992-1995
models
only)
7
-
1
--------------
Check
Engine
light
on
ENGINE-GENERAL
100-
1
1
Check
Engine
light
off
The
condition
of
the
fuel,
ignition
and
emission
controlsys-
tem
components
has
a
directeffect
onengineperformance
and
driveability
.
BMW
specifies
maintenance
of
certain
parts
at
regular
intervals
lo
keep
the
engine
in
proper
tune
.
Extend-
ing
maintenance
intervals
beyond
the
time
or
mileagerecom-
mended
bythe
manufacturer
can
adversely
affect
the
way
the
engine
runs
.
When
troubleshooting
driveability
problems,
a
good
starting
point
is
to
perform
a
major
engine
service,par-
ticularly
if
one
is
overdue
.
For
maintenance
schedules,
major
engine
service
and
other
driveability-related
maintenance
procedures,
see020
Maintenance
Program
.
Basic
Engine
Settings
2
.
Check
that
the
battery
isin
good
condition
.
Check
that
the
cables
are
tight
and
free
of
corrosion
at
both
ends
.
Idle
speed,
idle
mixture
(%CO),
and
ignition
timing
are
not
Check
that
all
related
ground
points
are
firmly
connect-
adjustable
.
The
adaptive
engine
management
system
is
de-
ed
and
in
good
condition
.
Check
al¡
harness
connectors
signed
lo
automatically
compensate
for
changes
in
engine
op-
for
damage
and
corrosion
.
erating
conditions,
although
the
adaptive
range
is
limited
.
Once
these
limits
are
exceeded,
driveability
problems
usually
3
.
Check
for
prwer
and
ground
at
the
Engine
Control
become
noticeable
.
Module
(ECM)
.
Check
the
main
grounds
for
the
ECM
.
See130
Fuel
Injection
.
NOTE-
If
the
DME
adaptive
limits
are
exceeded,
the
Check
En-
4
.
Check
the
fuses
.
Check
for
sufficient
fuel
in
the
tank
.
If
gine
light
will
come
on,
indicating
an
emission
related
the
engine
ranout
of
fuel,
it
will
take
a
little
time
to
re-
fault
.
See
130
Fuel
Injection,
store
fuel
pressure
.
See
160
Fuel
Tank
and
Fuel
Pump
.
Oxygen
Sensors
5
.
Check
for
spark
at
the
spark
plugs
.
If
the
tachometer
needle
bounces
while
the
engine
is
crankedby
the
A
high
oxygen
level
in
the
engine
exhaust
indicates
a
lean
starter
then
the
ignition
system
is
probably
working
cor-
air-fuel
mixture
and
a
low
oxygen
level
indicates
a
rich
mix
rectly
.
See
120
Ignition
System
.
ture
.
The
oxygen
sensor,
shown
in
Fig
.
10,
measures
the
oxy-
gen
content
in
the
exhaust
gasand
generates
a
variable
6
.
Check
for
any
faults
through
the
On-Board
Diagnostics
voltage
signal
.
Using
that
feedback
signal
asan
input,
the
system
.
See
On-Board
Diagnostics
(OBD)
.
DME
control
module
fine
tunes
the
air-fuel
mixture
.
DRIVEABILITY
TROUBLESHOOTING
113-10
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
Tightening
Torques
"
Coolant
drain
plug
to
cylinder
block
.
.
25
Nm
(18
ft-1b)
"
Intake
manifold
support
to
manifold
.
.
15
Nm
(11
ft-Ib)
"
Lower
intake
manifold
to
cylinder
head
.
..........
.
..
...
15
Nm
(11
ft-Ib)
"
Lower
intake
manifold
to
upper
manifold
..........
.
..
...
15
Nm
(11
ft-Ib)
"
Radiator
cooling
fan
to
coolant
pump
.
40
Nm
(30
ft-Ib)
"
Radiator
drain
screw
to
radiator
...
.
2
.5
Nm
(22
in-lb)
CYLINDER
HEAD,
6-CYLINDER
For
ease
of
use
this
procedure
is
broken
into
subsections,
as
follows
:
General
Coolingsystem,
draining
Cyiinder
head
cover,
removing
Intake
manifold,
removing
Timing
chains,
uncoupling
Cylinder
head
assembly,
removing
WARNING
-
Allow
the
engine
to
cool
before
beginning
this
pro-
cedure
.
General
1
.
Working
inside
luggage
compartment,
disconnect
neg-
ative
(-)
battery
cable
.
CAUTION-
"
Prior
to
disconnectiog
the
battery,
read
the
bat-
tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
vi¡¡
.
"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
control
module
memory
.
Check
for
fault
codes
using
special
BMW
diagnostic
equipment
2
.
Remove
front
exhaust
pipes
from
manifolds
.
Discard
nuts
.
3
.
Remove
air
filter
housing
complete
with
mass
air
flow
sensor
and
intake
air
ducting
.
Disconnect
vacuum
hos-
es
from
throttle
housing
.
4
.
On
M52
and
S52US
engines
:
Remove
secondary
air
injection
check-valve
from
front
of
engine
and
set
aside
.
CYLINDER
HEAD,
6-CYLINDER
Coolingsystem,
draining
5
.
Drain
engine
coolant
and
Rmove
coolant
hoses
from
thermostat
housing
.
Drain
engine
block
by
removing
block
drain
.
See
170
Radiator
and
Cooling
System
.
NOTE-
The
block
drain
is
on
the
exhaust
side
of
the
engine,
near
cylinder
no
.
5
.
6
.
Remove
radiator
cooling
fan
and
fan
shroud
.
See
170
Radiator
and
Cooling
System
.
NOTE-
The
radiator
cooling
fannut(32
mm
wrench)
has
left-
hand
threads
.
Cylinder
head,
removing
(6-cylinder
engine)
7
.
Disconnect
heater
hoses
at
rear
of
cylinder
head
.
See
Fig
.
26
.
'i
8
.
Remove
alternator
cooling
duct
.
Cylinder
head
cover,
removing
0012687
Fig
.
26
.
Disconnect
heater
hoses
at
heater
valve
(A)
and
heater
core
(B)
.
9
.
Remove
air
plenum
from
rear
of
engine
compartment
.
See640
Heating
and
Air
Conditioning
.
10
.
Remove
plastic
cylinder
head
covers
from
above
fuel
injectors
and
ignition
coils
.
Pull
larger
cover
forward
when
removing
.
See
Fig
.
27
.
11
.
Disconnect
crankcase
ventílation
hose
fitting
from
cyl-
inder
head
cover
.
12
.
Disconnect
ignition
coil
harness
connectors
from
coiis
.
Remove
ignition
coiis
and
spark
plugs
.
See
120
Igni-
tion
System
.
Camshaft
timing
chains,
removing
(6-cylinder
engines)
1
.
Disconnect
negative
(-)
cable
from
battery
.
CA
UTION-
Disconnecting
the
battery
may
erase
fault
codes)
stored
in
control
module
memory
.
Check
for
fault
codes
using
special
BMW
diagnostic
equipment
.
2
.
Drain
engine
coolant
.
Drain
engine
block
by
removing
block
drain
.
Remove
radiator
cooling
fan
shroud
and
cooling
fan
.
See170
Radiator
and
Cooling
System
.
.
WARNING
-
Allow
the
engine
to
cool
before
openingor
draining
the
system
.
CAUTION-
Radiator
fan
has
left
hand
threads
.
NOTE-
The
block
drain
plug
is
located
on
the
exhaust
side
of
the
engine,
below
cylinder
no
.
4
.
3
.
Drain
engine
oíl
andremove
oil
pan
.
See
119
Lubrica-
tion
System
.
4
.
Remove
alternator
cooling
duct
.
5
.
Remove
two
large
coolant
hoses
from
thermostat
housing
.
Remove
engine
lifting
bracket
and
thermostat
housing
from
front
of
cylinder
head
.
6
.
Loosen
bolts
for
coolant
pump
pulley
.
Then
remove
drive
belts
for
alternator
andA/C
compressor
.
See
020
Maintenance
Program
.
Remove
coolant
pump
pulley
.
Fig
.
16
.
NOTE-
OnM50
engines
with
a
two-roller
drive
belt
tensioner,
remove
the
upper
rollerto
access
thetensioner
mount-
ing
bolts
.
NOTE-
Make
note
of
the
arrangement
of
the
rubber
insulators
when
removing
the
cylinder
head
cover
mounting
bolts
.
CAMSHAFT
TIMING
CHAIN
117-
7
Fig
.
16
.
Drive
belt
tensioner
mounting
bolts
(arrows)
.
B11055
7
.
Remove
drive
belt
tensioner
from
front
of
engine
.
See
Fig
.
17
.
1992-1995
M50
engine
speed
sensor
on
timing
cover
(ar-
row)
.
10
.
Unclip
andremove
baffle
cover
from
above
intake
cam-
shaft
.
See
Fig
.
18
.
11
.
On
1992
engines
:
Remove
upper
timing
chain
cover
from
front
of
cylinder
head
.
See
Fig
.
19
.
8
.
Remove
engine
speed
sensor
from
lower
timing
chain
12
.
Loosen
spark
plugs
.
See
120
Ignition
System
.
cover,
if
applicable
.
See
Fig
.
17
.
13
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
9
.
Remove
cylinder
head
cover
.
See
113
Cylinder
Head
operating
direction
until
camshaft
lobes
at
cylinder
no
.
Removal
and
Installatíon
.
1
are
facing
each
other
.
See
Fig
.
20
.
14
.
Set
engine
to
TDC
by
aligning
"0/T'
mark
(0°TDC)on
front
vibration
damper
with
cast
bosson
lower
timing
chain
cover
.
See
Fig
.
21
.
15
.
Remove
vibration
damper
mounting
bolts
and
remove
vibration
damper
and
pulley
.
See
Fig
.
22
.
CAMSHAFT
TIMING
CHAINS,
6-CYLINDER
CHARGING
SYSTEM
TROUBLESHOOTING
.............
.
.
.
.
.121-2
Charging
System
Quick-Check
...
.
..
.
...
.
121-2
Static
current
draw,
checking
........
.
...
.
121-2
BATTERY
SERVICE
....................
121-3
Battery
Testing
.
.
.
.
.
.........
.
........
.
121-3
Hydrometer
Testing
.
...
.
.
.
...
.
.........
121-3
Battery
Open-Circuit
Voltage
Test
....
.
....
121-4
Battery
Load
Voltage
Test
.
.
.
.
.
.
.........
121-4
Battery
Charging
.
.
.
.
...
.
.
.
.
.
.
.
.........
121-4
ALTERNATOR
SERVICE
.
.
.
.
.
.
.....
.
...
121-4
Chargingsystem,checking
.
.
.
.
.
.........
121-4
Alternator,
removingand
installing
(4-cylinder
engine)
....
.
.
.
.
.
.
.
.........
121-5
Alternator,
removingand
installing
(6-cylinder
engine)
..
.
.
.
.
.
.
.
.
.
.........
121-6
GENERAL
The
charging
system
consists
of
a
belt-driven
alternator
with
integral
voltage
regulator
and
a
battery
mounted
in
the
luggage
compartment
.
Various
versions
of
alternators,
voltage
regulators,
starters,
and
batteries
are
used
in
the
E36
cars
.
It
is
important
to
re-
place
components
according
tothe
original
equipment
speci-
fication
.
Check
with
an
authorized
BMW
dealer
for
specific
application
and
parts
information
.
WARNING
-
"
Weargoggles,
rubbergloves,
and
a
rubberapron
when
working
around
batteries
and
battery
acid
(electrolyte)
.
"
Battery
acid
contains
sulfuric
acid
and
can
cause
skin
irritation
and
burning
.
ff
acid
is
spilled
onyour
skin
or
clothing,
flush
the
area
at
once
with
large
quantities
of
water
.
lf
electrolyte
gets
into
your
eyes,flush
them
with
largequantities
of
clean
wa-
terfor
several
minutes
and
call
a
physician
.
"
Batteries
that
are
being
charged
or
are
fully
charged
give
off
explosive
hydrogen
gas
.
Keep
sparks
and
open
flames
away
.
Do
not
smoke
.
BATTERY,
STARTER,
ALTERNATOR
121-1
121
Battery,
Starter,
Alternator
GENERAL
..
.
...
.
........
.
...
.
.
.
.
.
.
.
.
.
121-1
Voltage
regulator,
removing
and
ínstalling
.
.
.
121-6
Alternator
brushes,
inspecting
and
replacing
.121-7
STARTER
SERVICE
....
.
.
.
.
.
..........
.121-7
Starter
Troubleshootíng
121-7
15
..
.
.
.
.
.
........
.
.
.
Starter,
removing
and
installing
(4-cylinder
engine)
....
.
.
.
............
.
121-8
Starter,
removing
and
installing
(6-cylinder
engine
with
manual
transmission)
..
.
...........
.
...
121-8
Starter,
removing
and
installing
(6-cylinder
engine
with
automatic
transmission)
................
121-9
Solenoid
switch,
removingand
installing
....
121-10
TABLES
a
.
Battery,
Starter
and
Charging
System
Troubleshooting
............
.
.
.
.
:...
........
121-2
b
.
Specific
Gravity
of
Battery
Electrolyte
at
80°F
(27°C)
...............
.
.
..
..........
121-3
c
.
Open-Circuit
Voltage
and
Battery
Charge
........
121-4
d
.
Battery
Load
Test-Minimum
Voltage
.
..........
121-4
CAUTION
-
"
Prior
to
disconnectiog
the
battery,
read
the
bat-tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.
"
Disconnecting
the
battery
cables
may
erase
fault
codes
stored
in
control
unit
memory
.
"
Always
disconnect
the
negative
()
battery
cable
first
and
reconnect
it
last
.
Cover
the
battery
post
with
an
insulating
material
whenever
the
cable
is
removed
.
"
After
reconnecting
the
battery,
the
power
window
motors
must
be
reinitialized
.
See
511
Door
Win-
dows
.
"
Never
reverse
the
battery
cables
.
Even
a
momen-
tary
wrong
connection
can
damage
the
alternatoror
other
electrical
components
.
"
Battery
cables
may
be
the
same
color
.
Label
ca-blebefore
removing
.
GENERAL
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
.