warning BMW 325i 1994 E36 Owner's Manual
Page 41 of 759
NOTE-
Use
a14
mm
or17
mm
alíen
bit
socket
to
remove
the
drain
plug
.
"
If
thecar
is
raised
in
the
air,
it
shouldbe
leve¡
.
Fuel
tank
and
fuel
fines,
inspecting
0012474
Inspect
the
fuel
tank,
fuel
lines,
and
fuel
system
for
damage
or
leaks
.
Check
for
fuel
leaks
in
the
engine
compartment
or
fuel
odors
in
the
passenger
compartment
.
Check
for
faultyfuel
lines
bybending
them
.
If
any
leaks
are
present,
fuel
should
be
expelled
.
Check
for
any
evaporative
emissions
hoses
that
may
have
become
disconnected,
checking
carefully
at
the
charcoal
canister
and
evaporative
emissionspurge
system
.
See130
Fuel
Injection
and
160
Fuel
Tank
and
Fuel
Pump
for
component
locations
and
additional
information
.
WARNING
-
When
checking
for
fuel
leaks,
the
engine
must
be
cold
.
A
hot
exhaust
manifold
or
exhaust
system
could
cause
the
fuel
to
ignite
or
explode
causing
se-
rious
personal
injury
.
Uentilate
the
workarea
and
clean
up
spilled
fuel
immediately
.
Clutch
fluid,
checking
The
hydraulic
clutch
and
the
brake
system
share
the
same
reservoir
and
the
same
brake
fluid
.
Clutch
fluid
leve¡
and
brake
fluid
level
are
checked
at
the
same
time
.
See340
Brakes
for
more
information
.
See210
Clutch
for
information
on
the
clutch
and
the
hydraulic
clutch
operating
system
.
MAINTENANCE
PROGRAM
020-19
Drive
axie
joint
boots,
inspecting
100
Engine-General
The
protective
boots
must
be
closely
inspected
for
cracks
andany
other
damage
that
will
allow
contaminants
to
get
ínto
the
joint
.
If
the
rubber
boots
faf
,
the
water
and
dirt
that
enter
the
joint
will
quickly
damage
¡t
.
Replacement
of
the
drive
axle
joint
boots
and
inspection
of
the
joints
are
described
in
330
Rear
Suspension
.
BODY
AND
INTERIOR
MAINTENANCE
Windshield
Wiper
Biade
Maintenance
Common
problems
with
the
windshield
wipers
include
streaking
or
sheeting,
water
drops
after
wiping,
and
blade
chat-
ter
.
Streaking
is
usually
caused
when
wiper
blades
are
coated
with
road
film
or
car
wash
wax
.
Clean
the
blades
using
soapy
water
.
If
cleaning
theblades
does
not
cure
the
problem
then
they
should
be
replaced
.
BMW
recommends
replacing
the
wip-
er
blades
twice
a
year,
before
and
after
the
cold
season
.
Onold-
er
cars,
check
the
tension
spring
that
holds
the
wiper
to
the
glass
.
Replace
the
wiper
arm
if
the
springs
are
weak
.
Drops
that
remainbehind
after
wipingare
caused
by
oil,
road
film,
or
diesel
exhaust
coating
the
windshield
.
Use
an
alcohol
or
ammonia
solution,
or
a
non-abrasive
cleanser
to
clean
the
windshield
.
Wiper
blade
chatter
may
be
caused
by
dirty
or
worn
blades,
bya
dirty
windshield,
or
by
bentor
twisted
wiper
arms
.
Clean
the
blades
and
windshield
as
described
above
.
Adjust
the
wiper
arm
so
that
there
is
even
pressure
along
the
blade,
and
so
that
the
blade
is
perpendicular
to
the
windshield
atrest
.
Lubricate
the
wiper
linkage
with
a
light
oil
.
The
linkage
is
located
under
the
hood
on
the
drivers
side
.
If
the
problem
persists,
theblades
are
excessively
aged
or
worn
and
should
be
replaced
.
See
611
Wipers
and
Washers
.
Body
and
hinges,
lubricating
The
door
locks
and
lock
cylinders
canbe
lubricated
with
an
oil
that
contains
graphite
.
The
body
and
door
hinges,
the
hood
latch,
and
the
door
check
rods
should
be
lubricated
with
SAE
30
or
SAE
40
engine
oil
.
Lubricate
the
seat
runners
with
multipurpose
grease
.
Do
not
apply
any
oil
to
rubber
parts
.
If
door
weatherstrips
are
sticking,
lubricate
them
with
silicone
spray
or
talcum
powder
.
The
hood
release
cable
should
be
lubricated
as
well
.
The
use
of
winter
lock
de-icer
spraysshould
be
kept
to
an
ab-
solute
minimum,
as
the
alcohol
in
the
de-icer
will
wash
the
grease
out
of
the
lock
assemblies,
and
may
cause
the
locks
to
corrode
internally,
or
become
difficult
to
operate
.
ENGINE-GENERAL
100-1
Page 42 of 759
020-20
MAINTENANCE
PROGRAM
Seat
Belts
Washing
Chassis
Dirt
and
other
abrasive
particles
will
damage
seat
belt
web-
Periodic
washing
of
the
underside
of
the
car,
especially
in
bing
.
If¡t
is
necessary
to
clean
seat
belts,
use
a
mild
soap
solu-
winter,
will
help
prevent
accumulation
of
road
salt
and
rust
.
The
tion
.
Bleach
and
other
strong
cleaning
agents
may
weaken
the
besttime
to
wash
the
underside
is
just
after
the
car
has
been
belt
webbing
and
should
be
avoided
.
driven
in
wet
conditions
.
Spray
the
chassis
with
a
powerful
jet
of
water
.
Commercial
or
self-service
car
washes
may
not
be
best
WARNING-
for
this,
as
they
may
recycle
the
salt-contaminated
water
.
Do
not
clean
the
seat
belt
webbing
using
dry
clean-
ing
or
other
chemicals
.
Allow
wet
belts
to
dry
before
allowing
them
to
retract
.
Speeial
Cleaning
The
condition
of
the
belt
webbing
and
the
function
of
the
re-
tractor
mechanisms
should
be
inspected
.
See720
Seat
Belts
for
seat
belt
inspection
information
.
Exterior
Washing
The
longer
dirt
isleft
on
the
paint,
the
greater
the
risk
of
dam-
aging
the
glossy
finish,
either
by
scratching
or
by
the
chemical
effect
dirt
particles
may
have
on
the
paintedsurface
.
Do
not
wash
the
car
in
direct
sunlight
.
If
the
engine
hood
is
warm,
allow
it
to
cool
.
Beads
of
water
not
only
leavespots
when
dried
rapidly
by
the
sun
or
heat
from
the
engine,
but
also
can
act
as
small
magnifyingglasses
and
burn
spots
into
the
finish
.
Wash
thecar
with
a
mixture
of
lukewarmwater
and
a
car
wash
product
.
Rinse
using
plenty
of
clear
water
.
Wipe
the
body
dry
witha
soft
cloth
towel
or
chamois
to
prevent
water-spotting
.
Waxing
For
a
long-lasting,protective,
and
glossy
finish,
apply
a
hard
wax
after
thecar
has
been
washed
and
dried
.
Use
carnauba
or
synthetic
based
products
.
Waxing
is
not
needed
after
every
washing
.
You
can
tell
when
waxing
is
required
by
looking
at
the
finísh
when
it
is
wet
.
If
the
water
coats
the
paint
in
smooth
sheets
instead
of
forming
beads
that
rol¡
off,
a
new
coat
of
wax
is
needed
.
Wax
shouldnot
be
applied
to
black
trim
pieces,
rub-
ber,or
other
plastic
parts
.
Polishing
Use
paintpolish
only
if
the
finish
assumes
a
dull
lock
after
long
service
.
Polish
can
beused
to
remove
tar
spots
and
tar-
nish,
but
afterwards
a
coat
of
wax
should
be
applied
to
protect
the
clean
finish
.
Do
not
use
abrasive
polish
or
cleaners
on
alu-
minum
trimor
accessories
.
BODYAND
INTERIOR
MAINTENANCE
Cylinder
Head
and
Valvetrain
The
aluminum
cylinder
head
uses
chain-driven
double
overhead
camshafts
and
four
valves
per
cylinder
.
See
Fig
.
1
.
Tha
rvfinriar
hand
nmnlnve
n
ernceflnier
rineinn
fnr
nronter
Tar
spots
canbe
removed
with
a
bugand
tar
remover
.
Never
use
gasoline,
kerosene,
nail
polish
remover,
or
other
unsuitable
solvents
.
Insect
spots
also
respond
to
tar
remover
.
A
bit
of
bak-
ing
soda
dissolved
in
the
wash
water
will
facilitate
their
removal
.
This
method
can
also
beused
to
remove
spotting
from
tree
sap
.
Interior
Care
Dirt
spots
can
usually
be
removed
with
lukewarm
soapy
wa-
ter
or
a
dry
foam
cleaner
.
Use
spot
remover
for
grease
and
o¡I
spots
.
Do
not
pour
the
(quid
directly
on
the
carpetor
fabric,
but
dampen
a
clean
cloth
and
rub
carefully,starting
at
the
edge
of
the
spot
and
working
inward
.
Do
not
use
gasoline,
naptha,
or
other
flammable
substances
.
Leather
Upholstery
and
Trim
Leather
upholstery
and
trim
should
be
periodically
cleaned
using
a
slightly
damp
cotton
or
wool
cloth
.
The
idea
is
to
get
rid
of
the
dirtin
the
creases
and
pores
that
can
cause
brittleness
and
premature
aging
.
On
heavily
soiled
areas,
usea
mild
deter-
gent
(such
as
Woolite®)
or
other
specially
formulated
leather
r
cleaners
.
Use
two
tablespoons
to
one
quart
of
cold
water
.
Dry
the
trim
and
upholstery
completely
using
a
soft
cloth
.
Regular
use
of
agood
quality
leather
conditioner
will
reduce
drying
and
crackingof
the
leather
.
1
.
Camshafts
2
.
Rocker
arms
3
.
Hydraulic
valve
adjusters
(HVA)
4
.
Valve
and
conical
valve
spring
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 48 of 759
100-6
ENGINE-GENERAL
Cylinder
compression,
checking
A
compression
tester
is
needed
to
make
a
compression
test
.
To
obtain
accurate
test
results,
the
battery
and
starter
must
be
capable
of
cranking
the
engine
at
250-300
rpm,
and
theen-
gine
should
be
at
normal
operating
temperature
.
Use
com-
pressed
air
to
clean
aroundthe
spark
plugs
before
removal
.
1
.
Disable
the
ignítion
system
by
removing
the
engine
management
system
main
relay
and
the
fuel
pump
re-
¡ay
.
See
Fig
.
6
.
WARNING
-
The
ignítion
system
produces
high
voltages
that
canbe
fatal
.
Avoid
contact
with
exposed
termínals
and
useextreme
caution
when
working
on
acar
wíth
the
ignítion
switched
on
or
the
engine
running
.
Fuel
DM
E
pump
main
re
ay
rel
ay
o
oa
ooa
.,
o00
oao
Fig
.
6
.
Engine
management
relays
in
power
distribution
box
inleft
rear
of
engine
compartment
.
CAUTION-
"
On
OBD
11
cars,
making
a
compression
test
may
causea
faultto
set
in
the
ECM
and
may
also
il-
luminate
the
Check
Engine
light
.
The
light
can
only
be
tumed
out
using
special
scan
tool
equip-
ment,using
eíther
the
BMW
specialservíce
tool
or
using
a
"generic"
OBD
11
scan
tool
.
Discon-
necting
the
battery
will
not
erase
the
fault
mem-
orynor
turn
outthe
light
.
0013034,
0012630
Fig
.
7
.
Remove
spark
plug
wires
from
spark
plugs
on
4-cylinder
en-
gine
using
special
tool
.
Tool
is
stored
under
cover
at
rear
of
cylinder
head
(arrow)
.
Fig
.
8
.
Remove
engine
cover
on
6-cylinder
engine
byprying
off
nut
covers
and
removing
nuts
(A)
.
Be
careful
not
to
let
rubber
in-
sulators
fall
off
as
cover
is
removed
(arrows)
.
4
.
On
6-cylinder
engines,
disconnect
the
harness
connec-
tors
from
the
ignítion
coils
by
lifting
the
retaining
clip
.
Remove
the
coil
mounting
nuts
andremove
the
six
coils
.
See
Fig
.
9
.
Remove
the
sparkplugs
.
"
Failure
to
remove
the
main
relay
or
attempting
to
disable
the
ignítion
system
by
other
methods
may
resultin
damage
to
the
engine
control
module
.
NOTE-
Used
sparkplugs
should
be
reinstalled
in
the
same
cyl-
2
.
On
4-cylinder
engine
:
Remove
plastic
engine
cover
from
inder
fromwhich
they
were
removed
.
top
of
cylinder
head
.
Disconnect
spark
plug
wires
and
re-
move
spark
plugs
.
See
Fig
.
7
.
5
.
Insta¡¡
the
compression
gauge
in
the
first
cylinder's
3
.
On
6-cylinder
engine
:
Remove
top
engine
coverby
pry-
spark
plug
hole,
tight
enough
to
form
a
good
seal
.
ing
off
nut
covers
and
removing
mounting
nuts
.
See
Fig
.
8
.
MECHANICAL
TROUBLESHOOTING
Page 50 of 759
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
.
Page 59 of 759
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
Page 60 of 759
110-2
ENGINE
REMOVAL
AND
INSTALLATION
8
.
Drain
engine
coolant
andremove
coolant
hoses
at-
10
.
Remove
radiator
cooling
fan
and
radiator
as
described
tached
to
cylinder
head
.
in
170
Radiator
and
Cooling
System
.
"
Drain
radiator
and
engine
block
.
See
170
Radiator
and
Cooling
System
.
NOTE-
"
Disconnect
hoses
from
thermostat
housing
at
front
of
Some
late
4-cylinder
modelsuse
an
electric
prímary
cylinder
head
.
cooling
fan
.
"
Disconnect
heater
hoses
at
rear
of
engine
.
See
Fig
.
2
.
CAUTION-
NOTE-
On
cars
with
viscous-type
cooling
fans,
the
radia-
"
The
block
drain
plug
is
located
on
the
exhaust
side
to-
tor
fan
has
left
hand
threads
.
wards
rear
of
engine
.
"
Remove
small
plastic
lock
clíp
to
pull
radiator
drain
11
.
Remove
upper
intake
manifold,
unfasten
cable
duct
plug
out
completely
.
from
lower
intake
manifold,
crankcase
vent
valve
hose
(M44
engine
only)
0012687
Fig
.
2
.
Coolant
hoses
at
heater
valve
and
heatercore
to
be
discon-
nected
(arrows)
.
9
.
Remove
air
shroud
from
top
of
radiator
.
See
Fig
.
3
.
ENGINE
REMOVAL
AND
INSTALLATION
12
.
Disconnect
fuel
supply
and
fuel
return
lines,
main
en-
gine
electrical
connectors,
and
lower
intake
manifold
as
described
in
113
Cylinder
HeadRemoval
and
Instal-
lation
.
See
Fig
.
4
.
0012504
Fig
.
4
.
Crankcase
ventvalve
(A)
on
top
of
lower
intake
manifoldof
M44
engine
.
Fueldelivery
and
retum
lines
shown
at
B
.
Engine
harness
and
sensor
connectors
shown
at
C
.
WARNING
-
"
Fuel
may
be
expelled
under
pressure
.
Do
not
smoke
orworknear
heaters
or
other
fire
haz-
ards
.
Keep
a
fire
extinguisher
handy
.
Before
dis-
connecting
fuel
hoses,
wrap
a
cloth
around
fuel
hoses
to
absorb
any
leaking
fuel
.
Plug
all
open
fuel
lines
.
"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
lines
.
CAUTION-
0013137
I
Stuff
clean
rags
into
the
open
intake
ports
topre-
Fig
.
3
.
Front
air
shroud
mounting
screws
(arrows)
.
vent
any
parts
from
falling
into
the
engine
intake
.
13
.
Disconnect
vacuum
hose
from
brake
booster
on
bulk-
head
.
Cover
bothhole
in
booster
and
plug
hose
end
.
Page 62 of 759
110-
4
ENGINE
REMOVAL
AND
INSTALLATION
Engine,
removing
and
installing
(6-cylinder
engines)
Engineremoval
procedures
for
the
various
6-cylinder
en-
gines
arecovered
in
this
section
.
Most
steps
in
theproce-
dures
are
similar
or
the
same
for
al¡
engines
.
Specific
differences
that
apply
are
noted
at
the
beginning
of
each
step
.
Be
sure
to
cover
all
painted
surfaces
before
beginning
the
removal
procedure
.
As
an
aid
to
installation,
label
all
compo-
nents,wires,
and
hoses
before
removing
them
.
Do
not
reuse
gaskets,
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
(-)
battery
cable
in
luggage
com-
partment
.
CAUTION-
Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
vi¡¡
.
2
.
Remove
engine
hood
or
place
hood
in
service
position
.
See410
Fenders,
Engine
Hood
.
NOTE-
1t
is
not
necessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.
3
.
Remove
splash
guardunder
engine,
if
applicable
.
4
.
Remove
transmission
from
car
.
See
230
Manual
Transmission
or
240Automatic
Transmission
.
5
.
Remove
vacuum
hosefrom
brake
booster
on
bulkhead
.
Cover
hole
in
booster
and
plug
hose
end
.
6
.
Remove
intake
air
plenum
panel
in
rear
of
engine
com-
partment
.
See
640
Heating
and
AirConditioning
.
7
.
Remove
ground
strap
from
timing
case
cover,
if
appli-
cable
.
8
.
Remove
top
enginecovers
and
disconnect
ignition
coil
harness
connectors
.
Working
at
fuel
injectors,
pry
open
small
wire
clipsat
each
injector
.
Remove
main
harness
hold-down
nuts
and
lift
completeharness
away
.
See
Fig
.
7
.
ENGINE
REMOVAL
AND
INSTALLATION
Fig
.
7
.
Remove
mainharnessfrom
top
engine
and
place
at
base
of
windshield
.
0012703
Fig
.
8
.
Mass
air
flow
sensor
connector
air
duct
hose
clamp,
and
air
cleaner
housing
mounting
bolts
(arrows)
.
9
.
Unbolt
andremove
complete
air
cleaner
housing
with
10
.
On
cars
with
automatic
transmission,
remove
front
and
mass
air
flow
sensor,
disconnecting
and
labeling
con-
rearbrackets
holding
transmission
cooler
linesto
side
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
8
.
of
engine
.
Page 63 of 759
11
.
Draín
engine
coolant
and
Rmove
coolant
hoses
at-
tached
to
cylinder
head
.
"
Drain
engine
block
byremoving
block
drain
.
"
Disconnect
hoses
from
thermostat
housing
in
front
of
cylinder
head
.
"
Disconnect
heater
hoses
at
rear
of
engine
.
See
Fig
.
9
.
"
Drain
radiator
by
removingthreaded
plastic
plug
from
lower
left
comer
.
NOTE-
"
The
block
drain
plug
is
located
oh
the
exhaust
side
to-
wards
rear
ofengine
.
"
Remove
small
plastic
lock
clipto
pulíradiator
draín
plug
out
completely
.
NOTE-
CAUTION-
Radiatorfan
has
left
hand
threads
.
ENGINE
REMOVAL
AND
INSTALLATION
110-
5
Fig
.
9
.
Coolant
hoses
at
heater
valve
and
heater
core
to
be
discon-
nected
(arrows)
.
12
.
Remove
radiator
cooling
fan
and
radiator
as
described
in
170
Radiator
and
Cooling
System
.
13
.
Label
and
disconnectcoolant
hoses,
cables,
and
har-
ness
connectors
from
throttle
housing
.
See
Fig
.
10
.
14
.
Working
atrearof
intake
manifold,
label
and
then
re-
move
fuel
supply
and
fuel
retum
lines
.
Disconnect
fuel
lines
from
support
bracket
on
manifold
.
See
Fig
.
11
.
uu12ivu
Fig
.
10
.
Throttle
housing
assemblyon
M52
engine
.
Disconnect
hos-
es,
cables
and
harness
connectors
at
and
around
housing
.
0012699
Fig
.
11
.
Special
fuelline
fitting
at
fuel
rail
on
M52/S52US
engine
.
Use
BMW
special
tool
16
1
050
to
releaselocking
fittings
at
ends
offuel
lines
.
WARNING
-
"
Fuel
may
be
expelled
under
pressure
.
Do
not
smoke
or
work
near
heaters
or
other
fire
haz-ards
.
Keep
a
fire
extinguísher
handy
.
Before
dis-
connecting
fuel
hoses,
wrapa
cloth
around
fuel
hoses
to
absorb
any
leaking
fuel
.
Plug
all
oyen
fuel
fines
.
"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
ín
the
tank
before
working
on
the
tank
or
lines
.
OnM52
and
S52US
engines,
special
fittings
are
used
to
retain
the
fuel
lines
to
the
fuel
rail
.
Use
BMW
special
16
.
Remove
intake
manifold
from
engine
byremoving
sev-
tool
no
.
161050
to
compress
the
locking
clip
insidethe
en
mounting
nuts
from
above
andtwo
mounting
bracket
end
of
the
fuel
line
fittings
to
release
the
fine
.
boits
from
below
.
See
Fig
.
12
.
15
.
Unbolt
power
steering
fluid
reservoir
from
its
mounting
CAllTION-
bracket
.
Use
stiff
wire
to
hang
reservoir
to
one
side
.
Do
Stuff
clean
rags
into
the
open
intake
ports
to
pre-
not
disconnect
fluid
fines
.
vent
any
parts
from
falling
into
the
engine
intake
.
ENGINE
REMOVAL
AND
INSTALLATION