1995 BMW 323i board

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

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
.

Fig
.
16
.
Multimeter
or
Digital
Volt/Ohmmeter
(DVOM)
.

BMW
Special
Tools

FUNDAMENTALS
FOR
THE
DO-ITYOURSELF
OWNER
010-11

0012223

Some
of
the
more
challenging
repairs
covered
in
this
manual

cal¡
for
the
use
of
BMW
special
tools
.
This,
however,
does
not

automatically
mean
that
thejob
is
too
complicated
or
out
of

reach
of
thenovice
.

Many
of
the
BMW
special
tools
mentioned
in
this
manual
are
simplythe
best
thing
to
use
to
do
thejob
correctly
.
In
these
cas-

es,
the
tool
is
identified
with
a
BMW
part
number
.
See
your
au-

thorized
BMW
dealer
parts
department
for
information
on
how

to
order
special
tools
.

There
are
some
jobs
for
which
expensive
special
tools
are

essential,
and
not
a
cost-effective
purchase
for
one-time
repair

by
the
do-it-yourself
owner
.
This
manual
includes
such
repairs

for
the
benefit
of
these
with
the
necessary
experience
and
ac-

cess
to
tools
.
For
the
do-it-yourselfer,
the
need
for
special
tools

is
noted
in
the
text,
and
whether
or
not
BMW
dealer
service
is

recommended
.

EMERGENCIES

Changing
a
Tire

Stop
thecar
onas
flat
a
surface
as
possible,
in
a
place
where

you
canbe
easily
seen
by
other
drivers
.
Avoid
stopping
just

over
the
crest
of
a
hill
.
Turnon
the
emergency
flashers,
and
set

out
(lares
or
emergency
markers
well
behindthecar
.
Chock
the

wheel
(wheel
chock
located
in
trunk)
diagonally
opposite
to
the
one
being
changed
.
Passengers
shouldgetout
of
thecar
and

stand
well
away
from
the
road
.
Remove
the
spare
tire
from
the
spare
tire
storage
tray,
as
described
later
.

WARNING
-

If
a
tire
goes
fíat
while
drtving,
pull
well
off
the
road
.
Changing
a
tire
ona
busy
street
or
highway
is
very
dangerous
.
If
necessary,
drive
a
short
distance
on
the
fíat
tire
to
get
to
a
sale
place
.
tt
is
much
better
to
ruin
a
tire
or
rim
than
to
risk
being
hit
.

Take
the
jack
and
tools
from
the
tool
area
beneath
the
trunk

mat
.
Remove
the
spare
tire
from
the
tire
storage
tray
.

Loosen
the
wheel
bolts
while
the
car
is
on
the
ground,
but

leave
them
a
little
snug
.
Placethe
jack
in
the
lifting
point
nearest

the
wheel
beingchanged,
lifting
points
are
shown
in
Fig
.
1
and

Fig
.
2)
.
Use
a
board
to
provide
a
firm
footing
for
the
jack
if
the

ground
is
soft
.
Raise
the
car
only
lar
enough
so
that
the
wheel
is

fully
off
the
ground
and
then
remove
the
wheel
nuts
and
the

wheel
.

Insta¡¡
the
spare
wheel
.
Install
the
wheel
nuts
and
tighten

them
by
hand,
then
lower
the
car
.
With
all
wheelson
the

ground,
fully
tighten
the
nuts
in
a
crisscross
pattern
.
Torque
the

wheel
nuts
when
installing
the
wheel
.
Check
the
inflation
pres-

sure
of
the
spare
tire
.

Tightening
torques

"
Wheel
to
wheel
hub
.....
100
t
10
Nm
(74
t
7
ft-Ib)

Car
Will
Not
Start

If
the
engine
tucos
over
slowly
or
not
at
all,
especially
on
cold

mornings,
the
battery
may
not
be
sufficiently
charged
.
Jump-

starting
the
battery
from
another
car
may
help
.

WARNING
-

On
carswith
manual
transmisston,
push
starting
(or

tow
starting)
acar
ts
not
recommended
by
BMW
.

NOTE-

Be
sure
to
read
the
cautions
underJump
Starting
Car
prior
boosting
a
low
battery
.
Fatlure
to
followthe
cau-

tions
may
result
in
damage
to
the
electronic
compo-
nents
in
the
car
.

If
the
engine
is
turning
over
at
normal
speed
with
the
starter

motor,
the
battery
and
starter
are
fine
.
Check
to
make
sure
that

there
is
fuel
in
the
tank
.
Do
not
rely
on
the
fuel
gauge,
it
may
be

faulty
.
Instead,
remove
the
gas
filler
cap
and
rock
thecar
.
If

there
is
gas
in
the
tank,
you
should
hear
a
sloshing
sound
at
the

filler
neck
.
lf
there
is
plenty
offuel
in
the
tank,
see100
Engine-

General
for
in-depth
diagnostics
and
troubleshootingproce-

dures
.

EMERGENCIES

If
steam
is
coming
from
the
engine
compartment
thenthere
is



With
the
engine
and
ignition
off,
check
for
loose
or
corroded
most
likely
a
burst
coolant
hose
or
a
large
leak
in
the
cooling



battery
cables
or
wires
at
the
battery
or
thealtemator
.
Discon-
system
.
To
find
the
leak,
look
for
signs
of
coolant
leakage
on



necting,
cleaning,
and
reinstalling
corroded
wires
and
connec-
hoses,
at
hose
connections,
or
on
the
radiator
.
Let
theengine



tors
may
solve
the
problem
.
Also
check
drive
belt
tension
as
cool
thoroughly,
then
add
coolant
or
water
to
fill
the
system
and



described
in
020
Maintenance
Program
.
start
the
engine
.
If
a
great
deal
of
water
or
coolant
flows
out
of
the
hole,
then
thecarshouldnot
be
driven
until
repairs
are
made
.
lf
there
is
slight
seepage,
then
it
may
be
possible
to
drive



TOWi
ng

a
short
distance,
adding
coolant
as
needed
.
The
cars
covered
by
this
manual
should
be
towed
witha
tow
truck
using
wheel
lift
or
flat
bed
equipment
.
Do
not
tow
thecar
on
all
four
wheels
except
for
very
short
distances
to
move
it
to
a
safe
place
.
If
thered
engine
oil
pressure
warning
light
illuminates,
imme-
diately
stop
thecar
and
turn
off
the
engine
.
Have
the
vehicle



A
towing
eye
is
provided
in
the
luggage
compartment
tool
kit
.
flat-bedded
or
towed
to
an
authorized
service
center
and
have



The
towing
eye
can
be
screwed
into
the
front
or
rear
bumper
.
the
engine
oil
pressure
checked
.



See
Fig
.
18
and
Fig
.
19
.

Low
Oil
Pressure

NOTE-

Detafed
information
on
checking
the
oil
pressure
is
covered
ín
119
Lubrication
System
.

Brake
Fluid
Leve¡

The
brake
fluid
leve¡
warning
light
may
bean
indicator
of
brake
fluid
loss
.
Problems
with
the
brakesystem
should
be
checked
and
repaired
immediately
.
See
340Brakes
for
more

information
.

Check
Engine
Warning
Light

Dim
Lights

FUNDAMENTALS
FOR
THE
DO-IT
YOURSELF
OWNER



010-13

If
the
"CHECK
ENGI
NE"
warning
light
comes
on
or
flashes,
it
indicates
that
an
emissions-related
fault
has
occurred
.
Faults
suchas
a
failed
oxygen
sensor
or
a
faultyfuelinjector
can
tum

the
light
on,
causing
the
exhaust
or
evaporative
emissions
to

exceed
a
specified
limit
.
The
engine
can
be
safely
driven
with

the
light
on,
although
the
emission
systems
should
be
checked

assoonas
possible
.
See
100
Engine-General
for
more
infor-

mation
on
the
Check
Engine
Light
and
the
On-board
diagnostic

system
.

Headlights
and
instrument
panel
illuminationthat
are
dim
or

gradually
getting
dimmer
generally
indicate
a
problem
with
the

battery
or
charging
system
.
The
battery
charge
indicator
light

may
come
on
as
the
lights
are
dimming
.
In
either
case,
theen-

gine
and
accessories
are
running
off
of
the
battery
alone,
and

will
soon
discharge
it
altogether
.

If
possible,
do
not
stop
the
engine
unless
you
have
the
capa-

bility
to
jump
start
¡t
.
There
may
not
be
enough
power
in
the

starting
system
torestart
the
engine
.
Instead,turn
off
as
many

electrical
consumers
as
possible
.
This
will
reduce
the
current

drain
and
will
allow
thecar
to
be
driven
farther
before
you
lose

all
battery
power
.

Fig
.
18
.
Pry
open
rear
tow
lúg
access
panel
.

When
towingthecar
from
the
front
with
the
rear
wheelson

the
ground,
a
maximum
distance
of
20
miles
is
acceptable
.
If

thecar
needs
to
be
towed
further,
have
the
rear
wheels
placed
on
dollies
.

CA
UTION-

"
Do
not
tow
with
sling-type
equipment
The
front
spoilers
andbumper
covers
may
sustain
dam-
age
.

"
Towínga
BMW
with
an
automatic
transmission
with
the
rear
wheelson
the
ground
can
resuft
in
transmission
damage
due
to
lackof
lubrication
and
should
be
avoided
.

0013128

EMERGENCIES

Fig
.
18
.
Fill
mark
on
coolant
expansion
tank
.
Coolant
level
should
be

at
mark
when
engine
ís
cold
.

.
..
e
..
.-
..



~
..
.-
.

Ozone
Damaged
Hose

0012476

Fig
.
19
.
Examples
of
damage
to
coolant
hoses
.
Any
of
conditions

shown
is
cause
for
replacement
.
Courtesy
of
Gates
Rubber
Company,
Inc
.

Specification

"
Power
steering
fluid
..........
.
...
Dexron
III®ATF

Oxygen
Sensors

1996
and
later
engines
are
equipped
withmultiple
oxygen

sensors
.
See
Fig
.
21
.
A
regulating
sensor
is
mounted
before

each
catalytic
converter
and
amonitoring
sensor
downstream

of
each
converter
.
The
regulating
sensor
monitors
engine
com-

bustion
efficiency
and
helps
to
control
the
fuel
injection
system

and
exhaust
emissions
.
The
monitoring
sensor
is
usedby
the

On-board
diagnostic
system
to
monitor
the
function
of
the
cata-

lytic
converter
.

MAINTENANCE
PROGRAM



020-
1
5

NOTE-

5pecialsockets
for
replacingthe
oxygen
sensor
are

available
from
most
automotive
parts
stores
.
The
sock-

et
has
agroove
cut
down
one
side
to
allow
the
sensor

to
be
installed
without
damaging
the
wire
hamess
.

Fig
.
20
.
Power
steering
fluid
dipstick
showing
MIN
and
MAX
marks
.

OBD
II
enhanced
emission
standards
require
the
engine

control
module
(ECM)
to
monitor
the
oxygen
content
in
theex-

haust
bothbefore
and
after
the
catalytic
converter
.
This
allows

for
tightercontrol
of
the
tail
pipe
emissions
and
also
allowsthe

ECM
to
diagnose
converter
problems
.
lf
the
DME
detects
that

catalytic
converter
or
oxygen
sensor
efficiency
has
degraded

past
a
certain
pre-programmed
limit,
it
will
turn
on
the
Check

Engine
light,
and
store
a
diagnostic
trouble
code
(DTC)
in
the

ECM
.

Replacement
of
oxygen
sensors
at
the
specified
intervals
en-

sures
that
the
engine
and
emission
control
system
wíll
continue

to
operate
as
designed
.
Extending
the
replacement
interval

may
void
the
emission
control
warranty
coverage
.
See
180
Ex-

haust
System
for
information
on
replacing
the
oxygen
sen-

sors
.

Tightening
Torque

"
Oxygen
sensor
to

exhaust
system
........
.
.
.
..
55±5
Nm
(40±4
ft-Ib)

ENGINE
COMPARTMENT
MAINTENANCE

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

camshaft
secondary
drive,
causing
thecamshaft
to
"advance"

12
.5°
.
The
helical
gears
are
cut
so
that
forward
motion
of
the

gear
cup
is
transiated
into
rotational
motion
of
the
camshaft
.

See
117
Camshaft
Timing
Chain
for
testing
and
repair
infor-
mation
on
the
VANOS
system
.

DISA
(Dual
Resonance
Intake
System)

DISA,usedon
4-cylinder
engines,
is
a
dual
intake
runner

system
that
effectively
provides
the
advantages
of
both
short

and
long
intake
runners
within
the
same
engine
.
For
best
per-

formance,
long
intake
runners
aremost
beneficial
atlow-
and
mid-engine
speeds
(below
4,200
rpm),
and
short
intake
run-
ners
enhance
torque
at
high
engine
speeds
(above4,200
rpm)
.

NOTE-

The
term
DISA
comes
from
the
German
words
Differ-
enzierte
Sauganlage,
and
can
roughty
be
transiated
as
a
differing
intake
manifold
configuration
.

The
DISA
solenoid
valve
is
controlled
by
the
DME
control

module,
using
engine
speed
as
the
primary
input
.
The
main

components
of
the
system
are
the
modified
twin-section
in-

takemanifoldwith
change-over
valve,
the
twin-barrel
throttle

body,
and
the
electrical/pneumatic
actuating
components
.

See
Fig
.
4
.

r

I

I

I

?
,
in
UpPer,
take
-1
manifold

1
-1
Throttle
housing
(Heated)

q
:lZU

Fig
.
4
.



DISA
system
components
.
DISA
changes
the
intake
runner

length
based
on
engine
speed
.

The
DISA
system
electro-pneumatically
changes
the
intake
runner
length
through
the
twin-section
intake
manifold
and
a
change-over
butterfly
valve
.
The
change-over
valve
is
located
at
a
point
in
the
intake
manifold
where
four
pipes
come
into
two
.
When
the
change-over
valve
is
closed,
the
4-way
primary
intake
manifold
and
the
2-way
ram
air
manifold
areconnected
to
make
the
"long"
configuration
.
When
the
change-overvalve
opens,
intake
air
flow
is
redirected
through
only
the
short
4-

way
primary
intake
manifold
.

The
change-over
valve
is
held
in
the
normally
open
position
bya
spring
.
Thisallows
for
an
open
valve
in
the
event
of
sys-
tem
failure
.
During
low
andmid
enginespeeds,
the
DME
con-

trol
module
supplies
power
to
the
solenoid
valve,
which
in
turn

allows
vacuum
to
be
applied
lo
the
vacuum
diaphragm
.
This

causes
the
valve
to
close
(long-pipe
configuration)
.
When
en-
gine
speed
reaches
approximately
4,800
rpm,
the
DME
con-
trol
module
electrically
signals
the
solenoid
valve
and
the
valve
opens,
creating
the
short
pipe
configuration
:

Further
detafs
on
DISA
canbefound
in
130
Fuel
Injection
.

Engine
Management
System

Al¡
enginescoveredby
this
manual
usean
advanced
engine

management
system
called
Digital
Motor
Electronics
(DME)
.

In
the
DME
system,
advancedOn-Board
Diagnostics
(OBD),

fuel
injection,
ignition,
and
otherfunctions,
are
combined
under

the
control
of
theEngine
Control
Module
(ECM)
.
See
Fig
.
5
.

-



Lower
intake
manifold

DISAvacuum
'
~servo

EíY1z

ENGINE-GENERAL
100-
3

le

-
DISA
solenoid
valve

0012591

/
with
butterfly
va¡

GENERAL