General
Data
and
010
FundamentalsfortheDo-lt-YourselfOwner
Maintenance
020
Maintenance
Program
Engine
Transmission
Suspension,
Steering
and
Brakes
4
Body
100
Engine-General
110
Engine
Removal
and
Installation
113
Cylinder
Head
Removal
and
Installation
116
Cylinder
Head
and
Valvetrain
117
Camshaft
Timing
Chain
119
Lubrication
System
200
Transmission-General
210
Clutch
230
Manual
Transmission
510
Exterior
Trim,
Bumpers
520
Seats
Bo
y
Equipment
512
DoorWTdws
540
nr
t
513
InteriorTrim
541
Convertible
Top
515
Central
Locking
and
Anti-Theft
600
Electrical
System-General
620
Instruments
Electrical
S
stem
610
Electrical
Component
Locations
630
Exterior
Lighting
611
Wipers
and
Washers
640
Heating
and
Air
Conditioning
6
612
Switches
and
Electrical
Accessories
650
Radio
Equipment
and
720
SeatBelts
Accessories
721
Airbag
System
(SRS)
Electrical
Wiring
Diagrams
Foreword
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v
Warnings
and
Cautions
.....
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.vii
Index
..............
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.
.
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.
.
.
..
back
of
book
300
Suspension,
Steering
and
330
RearSuspension
Brakes-General
331
Final
Drive
310
Front
Suspension
340
Brakes
320
Steering
and
Wheel
Alignment
400
Body-General
411
Doors
410
Fenders,
Engine
Hood
412
Trunk
Lid
120
Ignition
System
121
Battery,Starter,
Alternator
130
Fue¡
Injection
160
Fuel
Tank
and
Fuel
Pump
170
Radiator
and
Cooling
System180
Exhaust
System
240
Automatic
Transmission
250
Gearshift
Linkage
260
Driveshaft
Please
read
these
warnings
and
cautions
before
proceeding
with
maintenance
and
repair
work
.
WARNING-
"
Friction
materials
(such
as
brake
pads
or
shorts
or
clutchdiscs)
contain
asbestos
fibers
or
other
friction
materials
.
Do
notcreate
"
See
also
Cautionson
page
viü
dustby
grinding,
sanding,
orby
cleaning
with
compressed
air
.
"
Some
repairs
may
be
beyond
your
capability
.
If
you
lack
the
Avoid
breathing
dust
.
Breathing
any
friction
material
dust
can
lead
skills,
tools
and
equipment,
or
a
suitable
workplace
for
any
proce-
to
serious
diseases
and
may
result
in
death
.
duredescribed
in
this
manual,
we
suggestyou
leave
such
repairs
"
Batteries
give
off
explosive
hydrogen
gas
during
charging
.
to
an
authorized
BMW
dealer
service
department
or
other
quali-
Keep
sparks,
lighted
matches
and
open
flame
away
from
the
top
fied
shop
.
of
the
battery
If
hydrogen
gas
escaping
from
the
cap
vents
is
"Do
not
re-use
any
fasteners
that
are
worn
or
deformed
in
normal
ignited,
it
will
ignite
gas
trapped
in
the
cells
and
cause
the
battery
use
.
Many
fasteners
are
designed
to
be
used
only
once
and
to
explode
.
become
unreliable
and
may
fail
when
used
a
second
time
.
This
"
Connect
and
disconnect
battery
cables,
jumper
cablesora
bat-
includes,
but
is
not
limited
to,
nuts,
bolts,
washers,
self-locking
nuts
or
bolts,
circlips
and
cotterpins
.
Always
replace
these
fasteners
with
new
parts
.
"Do
not
quick-charge
the
battery
(for
boost
starting)
for
longer
"
Never
work
under
a
lifted
car
unless
it
is
solidly
supportedon
than
one
minute
.
Wait
at
least
one
minute
before
boosting
the
bat-
stands
designed
for
the
purpose
.
Do
not
support
a
car
on
cinder
tery
a
second
time
.
blocks,
hollow
tiles
or
other
props
that
may
crumble
under
contin-
uous
load
.
Never
work
under
acar
that
is
supported
solely
by
a
"Do
not
allow
battery
charging
voltage
to
exceed
16
.5
volts
.
If
the
jack
.
Never
work
under
thecar
while
the
engine
is
running
.
battery
beginsproducing
gas
or
boiling
violently,
reduce
the
charg-
ing
rate
.
Boosting
a
sulfated
battery
at
a
high
charging
rate
can
"
If
you
are
going
to
work
under
acar
on
the
ground,
make
sure
cause
an
explosion
.
that
the
ground
is
level
.
Block
the
wheels
to
keep
the
carfrom
roll-
ing
.
Disconnect
the
battery
negative
(-)
terminal
(ground
strap)to
"
The
air-conditioning
system
is
filled
with
chemical
refrigerant,
prevent
others
from
starting
thecar
while
youare
under
it
.
which
is
hazardous
.
TheA/C
system
should
be
servicedonly
by
trained
technicians
using
approved
refrigerant
recovery/recycling
"
Never
run
the
engine
unless
the
work
area
is
well
ventilated
.
equipment,
trained
in
related
safetyprecautions,
and
familiar
with
Carbon
monoxide
kills
.
regulations
governing
the
discharging
and
disposal
of
automotive
"
Finger
rings,
bracelets
and
other
jewelry
shouldbe
removed
so
chemical
refrigerants
.
tery
charger
only
with
the
ignition
switched
off,
to
prevent
sparks
.
Do
not
disconnect
the
battery
while
the
engine
is
running
.
that
theycannot
cause
electrical
shorts,
get
caught
in
running
"
Do
not
expose
any
partof
the
A/Csystem
to
high
temperatures
machinery,
or
be
crushed
by
heavy
parts
.
suchas
open
flame
.
Excessiveheat
will
increase
system
pressure
"
Tie
long
hair
behind
your
head
.
Do
not
wear
a
necktie,
a
scarf,
and
may
cause
the
system
to
burst
.
loose
clothing,
or
a
necklace
when
you
work
near
machine
tools
or
"
Some
aerosol
tire
inflators
are
highly
flammable
.
Be
extremely
running
engines
.
If
your
hair,
clothing,
or
jewelry
were
to
get
caught
cautious
when
repairing
a
tire
that
may
havebeen
inflated
using
in
the
machinery,
severe
injury
could
result
.
an
aerosol
tire
inflator
.
Keep
sparks,
open
flame
or
other
sources
"
Do
not
attempt
to
work
onyourcar
if
you
do
not
feel
well
.
You
of
ignition
away
from
the
tire
repair
area
.
Inflate
and
deflate
the
tire
increase
the
danger
of
injury
toyourself
and
others
if
you
are
tired,
at
least
four
times
before
breaking
the
bead
from
therim
.
Com-
upset
or
have
takenmedication
or
any
other
substance
that
may
Pletely
remove
the
tire
from
the
rim
beforeattempting
any
repair
.
keep
you
from
being
fully
alert
.
"
Illuminate
your
work
areaadequately
but
safety
.
Use
a
portable
safety
light
for
working
inside
or
under
thecar
.
Make
surethe
bulb
is
enclosedbya
wire
cage
.
The
hot
filament
of
an
accidentally
bro-
ken
bulb
can
ignite
spilled
fuel
or
oil
.
"
Catch
draining
fuel,
oil,
orbrake
fluid
in
suitable
containers
.
Do
not
use
food
or
beverage
containers
that
mightmislead
someone
into
drínking
from
them
.
Store
flammable
fluids
away
from
fire
haz-
ards
.
Wipe
up
spills
at
once,
but
do
not
store
the
oily
rags,
which
can
ignite
and
burn
spontaneously
.
"
Always
observe
good
workshop
practices
.
Wear
goggles
when
youoperate
machine
tools
or
work
with
battery
acid
.
Gloves
or
other
protectioeclothing
should
be
worn
whenever
thejob
requires
working
with
harmful
substances
.
"
Greases,
lubricants
and
other
automotive
chemicals
contain
toxic
substances,
many
of
which
are
absorbed
directly
through
the
skin
.
Read
the
manufacturer's
instructions
and
warnings
carefully
.
Use
hand
andeye
protection
.
Avoid
direct
skin
contact
"
Cars
covered
by
this
manual
are
equipped
with
a
supplemental
restraint
system
(SRS),
that
automatically
deploys
an
airbag(s)
in
theevent
of
a
frontal
ímpact
.
The
airbag(s)
is
inflated
byan
explo-
sive
device
.
Handled
improperly
or
without
adequate
safeguards,
can
be
accidently
activated
and
cause
serious
injury
.
"
The
ignition
system
produces
high
voltages
that
can
be
fatal
.
Avoid
contact
with
exposed
terminals
and
use
extreme
care
when
working
ona
car
with
the
engine
running
or
the
ígnition
switched
on
.
"
Place
jack
stands
only
at
locations
specified
bymanufacturer
.
The
vehicle
lifting
jacksupplied
with
the
vehicle
is
intended
for
tire
changes
only
.
A
heavy
duty
floor
jack
shouldbe
used
to
lift
vehicle
before
installing
jack
stands
.
See
010
Fundamentals
for
theDo-
.
it-Yourself
Owner
.
"
Battery
acid
(electrolyte)
can
cause
severeburns
.
Flush
contact
area
with
water,
seek
medical
attention
.
"
Aerosolcleaners
and
solvents
may
contain
hazardous
ordeadly
vapors
and
are
highly
flammable
.
Use
only
in
a
wellventilated
area
.
Do
not
use
on
hot
surfaces
(engines,
brakes,
etc
.)
.
"
Disconnect
the
battery
negative
(-)
terminal
(Ground
strap)
"
Do
not
remove
coolant
reservoir
or
radiator
cap
with
theengine
whenever
you
work
on
the
fuel
system
orthe
electrical
system
.
Do
hot
.
Danger
of
bums
and
engine
damage
.
not
smoke
or
work
near
heaters
or
other
fire
hazards
.
Keep
an
approved
fire
extinguisher
handy
.
continued
on
next
page
vii
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
.
WARNING
-
"
Never
work
under
a
lifted
car
unless
it
is
solidly
supported
on
jack
stands
that
are
intended
for
that
purpose
.
Do
not
support
a
car
on
cinder
blocks,
bricks,
or
other
objects
that
may
shift
orcrumble
under
continuous
load
.
Never
work
un-
dera
car
that
is
supported
only
by
the
lifting
jack
.
"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
smoke
or
worknear
heaters
or
other
fire
hazards
.
Keepan
approved
fire
extinguisher
handy
.
"
llluminate
the
work
area
adequately
and
safely
.
Use
a
portable
safety
light
for
working
inside
or
under
thecar
.
A
fluorescent
type
lightis
best
be-
cause
it
gives
off
less
heat
.
If
using
a
light
with
anormal
incandescent
butb,
use
rough
service
bulbs
to
avoid
breakage
.
The
hot
filamentof
an
accidentallybroken
bulb
can
ignite
spilled
fuel
or
oil
"
Keep
sparks,
lighted
matches,
and
any
open
llame
away
from
thetop
of
the
battery
.
Hydrogen
gas
emitted
by
the
battery
is
highly
flammable
.
Any
nearby
source
of
ignition
may
cause
the
battery
to
explode
.
"
Never
¡ay
tools
or
parts
in
the
engine
compart-
ment
or
on
top
of
the
battery
.
They
may
fall
into
confined
spaces
and
be
difficult
toretrieve,
be-
come
caught
in
beits
or
other
rotating
parts
when
the
engine
is
started,
or
cause
electrical
shorts
anddamage
to
the
electrical
system
.
"
The
fuel
system
is
designed
to
retain
pressure
even
when
the
ignition
is
off
.
When
working
with
the
fuel
system,
loosen
the
fuel
fines
slowly
to
al-
low
the
residual
pressure
to
dissipate
gradually
.
Take
precautions
to
avoid
spraying
fuel
.
Lifting
the
Car
FUNDAMENTALS
FOR
THE
DO-ITYOURSELF
OWNER
010-
3
For
those
repairs
that
require
raising
the
car,
theproper
jack-
ing
points
should
beused
to
raise
thecar
safely
and
avoid
dam-
age
.
There
are
four
jacking
points
from
which
thecar
can
be
safely
raised
.
The
jacksupplied
with
thecar
by
BMW
can
only
be
used
at
the
fourside
points
just
behindthe
front
wheel
or
just
in
frontof
the
rear
wheel
.
See
Fig
.
1.
WARNING
-
"
When
raising
the
car
using
a
floor
jack
ora
hy-
draulic
lift,
carefully
position
the
jack
pad
topre-
vent
damaging
the
car
body
.
A
suitable
liner
(wood,
rubber,
etc
.)
should
be
placed
between
the
jack
and
the
car
to
prevent
body
damage
.
"
Watch
the
jack
closely
.
Make
sure
ft
stays
stable
and
does
not
shift
or
tilt
.
As
the
car
is
raised,
the
car
may
rol¡
slightly
and
the
jack
may
shift
.
Fig
.
1
.
3-Seriesjacking
points
(arrows)
.
Raising
car
safely
1
.
Park
car
on
flat,
leve¡
su
rface
.
2
.
Remove
the
round
cover
from
jack
mount
using
a
screwdriver
.
See
Fig
.
2
.
0013126
Fig
.
2
.
Jack
mount
cover
being
removed
from
rocker
panel
.
3
.
Place
jack
fully
into
position
.
See
Fig
.
3
.
Make
sure
jack
is
resting
on
flat,
solid
ground
.
Use
a
board
or
other
sup-
port
to
provide
a
firm
surface
for
the
jack,
if
necessary
.
4
.
Raisecar
slowly
while
constantly
checking
position
of
jack
and
car
.
5
.
Once
car
is
raised,
block
the
wheel
that
is
opposite
and
farthest
from
jackto
prevent
car
fromunexpectedly
roll-
ing
.
GET77NG
STARTER
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
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
.
110
Engine
Removal
and
Installation
GENERAL
.
.
.
.
.......
.
.
.
..........
.
...
110-1
Engine,
removing
and
installing
(4-cylinder
engines)
.
..
.....
..
...........
110-1
ENGINE
REMOVAL
AND
INSTALLATION
110-1
Engine,
removing
and
installing
(6-cylinder
engines)
..
...
...
..
.....
..
....
110-4
GENERAL
Some
special
tools
are
required
for
removal
and
installation
of
the
engine
.
Be
sure
to
have
the
necessary
equipment
on
hand
before
starting
thejob
.
CAUTION-
"
Engine
removal
requires
disconnecting
the
bat-
tery
.
This
may
erase
any
system
fault
code(s)
that
havebeen
stored
in
control
unit
memories
.
Check
forfault
codes
prior
to
disconnecting
the
battery
cables
.
"
If
the
Check
Engine
lightis
illuminated
with
the
engine
running,
see
100
Engine-General
for
On-Board
Diagnostics
(08D)
fault
code
infor-
mation
.
"
If
any
other
system
faults
have
been
detected,
as
indicated
by
an
illuminated
ANTI
LOCK,
SRS
or
AST
warning
light,
see
the
appropriate
repair
group
inthis
manual
or
an
authorized
BMW
dealer
for
more
information
on
fault
codes
.
ENGINE
REMOVALAND
INSTALLATION
Engine,
removing
and
installing
(4-cylinder
engines)
Cover
al¡
painted
surfaces
before
beginning
theremoval
procedure
.
Asan
aid
to
installation,
label
al¡
components,
wires,
and
hoses
before
removing
them
.
Do
not
reuse
gas-
kets,
O-rings
or
seals
during
reassembly
.
WARNING
-
Due
to
risk
of
personal
injury,
be
sure
the
engine
is
cold
before
beginning
the
removalprocedure
.
1.
Disconnect
negative
(-)
cable
from
battery
in
luggage
compartment
.
0011969
CAUTION-
Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.
ENGINE
REMOVAL
AND
INSTALLATION
110-1
2
.
Remove
transmission
from
car
.
See230
Manual
Transmission
or
240
Automatic
Transmission
.
3
.
Remove
enginehood
or
place
hood
in
service
positíon
.
See
410
Fenders,
Engine
Hood
.
NOTE-
tt
is
notnecessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.
4
.
Remove
splash
guard
under
engine,
if
applicable
.
5
.
Unbolt
ignition
coil
assembly
from
bracket
on
strut
tow-er
.
Disconnect
wiring
to
ignition
cofs,
then
place
coil
assembly
on
engine
.
6
.
Disconnect
al¡
cables
and
harness
connectors
at
throt-
tle
housing
.
7
.
Unbolt
andremove
complete
air
cleaner
housing
with
mass
air
flow
sensor,
disconnecting
and
labeling
con-
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
1
.
Fig
.
1
.
Intake
air
duct
hose
clamp
(A),
mass
air
flow
sensor
connec-
tor
(B),
and
air
cleanerto
air
flow
sensor
clips
(C)
on
M44
en-
gine
.
ENGINE
REMOVAL
AND
INSTALLATION