1997 BMW 328i vacuum
[x] Cancel search: vacuumPage 43 of 759
GENERAL
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100-1
Cylinder
Block
and
Crankshaft
.
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100-1
Connecting
Rods
and
Pistons
.
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100-1
Cylinder
Head
and
Valvetrain
.
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100-2
VANOS
(Variable
Valve
Timing)
.
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100-2
DISA
(Dual
Resonance
Intake
System)
.
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.
100-3
Engine
Management
System
.
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100-3
Ignition
......
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100-5
Fuel
Delivery
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100-5
Cooling
System
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100-5
Lubrication
System
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100-5
MECHANICALTROUBLESHOOTING
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100-5
Warnings
and
Cautions
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100-5
Cylinder
compression,
checking
.
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100-6
EngineMechanical
Troubleshooting
Table
.
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.
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)
...
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100-8
Basic
Requirements
....
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.100-11
Preventive
Maintenance
......
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100-11
Basic
Engine
Settings
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100-11
Oxygen
Sensors
.
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.100-11
Air
Flow
Measurement
and
Vacuum
Leaks
.
.100-12
Battery
Voltage
.
.
...........
.
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.....
100-12
Wiring
and
Harness
Connections
.
.
.
.
.....
100-13
Ground
Connections
...
.
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.
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100-13
Fue¡
Supply
....
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...........
.
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.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 45 of 759
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
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 54 of 759
100-
1
2
ENGINE-GENERAL
NOTE-
The
oxygen
sensor
signal
is
ignored
until
the
engine
reachesa
specified
minimum
temperature
.
Therefore,
The
primary
input
usedby
the
fuel
injection
system
to
deter-
when
troubleshooting
cold
engine
driveability
prob-
mine
how
much
fuel
should
be
delivered
is
the
signal
from
the
lems,
the
oxygensensor
canbe
ruled
out
asa
possible
mass
air
flow
sensor
in
the
intake
air
ductwork
.
cause
.
As
the
oxygen
sensor
ages,
its
ability
to
react
quickly
to
changing
conditions
deteriorates,
and
it
may
eventually
cease
to
produce
any
signal
at
all
.
To
check
the
operation
of
the
oxy-
gen
sensor,
see
130
Fuel
Injection
:
NOTE-
On
1996
and
latercars,
OBD
11
enhanced
emission
standards
require
the
engine
control
module
(ECM)
to
monitor
the
oxygen
content
in
the
exhaust
both
before
and
after
the
catalytic
converter
.
Thisallows
for
tighter
control
of
the
tail
pipe
emissions
and
also
allowsthe
ECM
to
diagnose
converter
problems
.
If
the
DME
de-
tects
that
catalytic
converter
or
oxygensensor
efficien-
cyhas
degraded
pasta
certain
pre-programmed
limit,
it
will
turn
on
the
Check
Engine
light,
and
store
a
diag-
nostic
trouble
code
(DTC)
in
the
ECM
.
DRIVEABILITY
TROUBLESHOOTING
Catalytic
B9506
Air
Flow
Measurement
and
Vacuum
Leaks
Because
proper
fuel
metering
depends
on
accurate
mea-
surement
of
the
incoming
air,
any
unmeasured
air
that
enters
the
engine
downstream
of
the
mass
air
flow
sensor
will
cause
a
lean
air-fuel
mixture
and
possibly
affectdriveability
.
NOTE-
Fig
.
10
.
Regulating
oxygen
sensor
measures
oxygen
content
of
ex-
gattery
Voltage
hausY
gas
as
indicator
of
.¡_fi
.1
ratio
and
"-k,
.
E-
effi-
ciency
.
Monitoríng
oxygen
sensor
(not
shown)
monitors
If
a
large
air
leak
is
causing
driveability
problems,
the
Check
Engine
light
will
usually
be
illuminated
and
a
fault
will
be
stored
in
the
fault
code
memory
.
See
On
Board
Diagnostics
(OBD)
.
There
are
many
places
for
unmeasured
air
to
enter
theen-
gine
.
First,
inspect
all
hoses,
fittings,
ducts,
seals,
and
gaskets
in
the
intake
air
tract
for
cracks
or
looseness
.
It
may
be
neces-
sary
to
remove
parts
that
cannot
be
fully
checked
in
their
in-
stalled
positions
.
Also
make
sure
all
of
the
intake
manifold
and
throttle
body
mounting
nuts
are
tight
.
In
addition
to
air
leaks,
air
restrictions
can
also
cause
drive-
ability
problems
.
Remove
the
air
filter
and
hold
it
up
to
a
strong
light
source
.
If
the
filter
does
not
pass
light,
it
is
restricted
and
should
be
replaced
.
Also,
remove
the
intake
air
ductwork
and
check
for
oily
deposits
at
the
throttle
plate
.
Buildup
in
this
area
can
cause
an
erratic
idle
.
Clean
away
any
deposits
using
a
cloth
wetted
withcarburetor
cleaner
and
reinstall
the
ductwork
.
CAUTION-
Do
not
spray
carburetor
cleaner
directly
in
the
throt-
tle
anea
.
Spraying
cleaner
may
force
it
into
the
throt-
tle
position
switch
or
sensor
and
cause
damage
.
catalytic
converter
operation
.
All
of
the
electrical
components
in
the
fuelinjection
and
igni-
tion
systems
require
a
minimum
voltage
to
operate
properly
.
When
troubleshooting
engine
driveability
problems,
one
of
Replacement
of
oxygensensors
at
the
specified
intenrals
en-
the
first
checks
should
be
to
make
sure
the
battery
is
fully
sures
that
the
engine
and
emission
control
system
wili
continue
charged
and
capable
of
delivering
allits
power
to
the
electricalto
operate
as
designed
.
As
the
oxygen
sensor
ages,
its
ability
to
system
.
react
quickly
to
changing
conditions
deteriorates,
and
it
may
eventually
cease
to
produceany
signal
at
all
.
To
make
a
quick
check
of
battery
charge,
measure
the
volt-
age
across
the
battery
terminals
with
all
cables
attached
and
As
the
oxygen
sensor
ages,
its
ability
to
react
quickly
to
the
ignition
off
.
A
fully
charged
battery
will
measure
12
.6
volts
changing
conditions
deteriorates,
and
it
may
eventually
cease
or
slightly
more,
compared
to
12
.15
volts
for
a
battery
with
a
to
produce
any
signal
at
all
.
To
check
theoperation
of
the
oxy-
25%
charge
.
gen
sensor,
see130
Fuel
Injection
.
Even
a
fully
charged
battery
cannot
deliver
power
unless
it
is
properly
connected
to
the
electrical
system
.
Check
the
bat-
tery
terminals
for
corrosion
and
loosecableconnections
.
If
the
battery
does
not
maintain
the
proper
voltage,
the
charging
system
may
be
atfault
.
See
121
Battery,
Starter,
Alternator
.
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 67 of 759
113
Cylinder
Head
Removal
and
Installation
GENERAL
.
...............
.
.
.
.
.
.......
113-1
CYLINDER
HEAD,
6-CYLINDER
.
.
.
.
.
.
.
113-10
Cylinder
head,
removing
(6-cylinder
engine)
..
113-10
CYLINDER
HEAD,
4-CYLINDER
..
.
...
.
.
113-1
Cylinder
head,
installing
(6-cylinder
engine)
...
113-15
Cylinder
head,
removing
(4-cylinder
engine)
...
113-1
E
Cylinder
head,
installing
(4-cylinder
engine)
...
113-6
GENERAL
CYLINDER
HEAD,
4-CYLINDER
The
information
given
inthis
repair
group
assumes
that
the
engine
is
installed
in
the
engine
bay
.
For
cylinder
head,
cam-
Cylinder
head,
removing
shaft,
and
valvetrain
disassembly
and
reconditioning
informa-
(4-cylinder
engine)
tion,
see116
Cylinder
Head
and
Valvetrain
.
For
ease
of
use
this
removal
procedure
is
broken
into
sub-
In
the
procedures
given
below,
engines
are
referred
to
by
sections,
as
follows
:
engine
code
.
If
necessary,
see100
Engine-General
for
en-
gine
code
and
application
information
.
NOTE-
If
a
head
gasket
problem
is
suspected,
acompression
test
will
usually
detectthe
fault
.
See
100
Engine-Gen-
eral
for
compression
testing
information
.
Special
BMW
service
tools
are
required
to
properly
remove
and
install
the
cylinder
head
on
both
the
4-cylinder
and
6-cyl-
inder
engines
.
The
special
tools
are
used
to
time
the
val-
vetrain
to
the
crankshaft
and
to
remove
the
Torx
(El
2)
head
bolts
.
Read
the
procedure
through
before
beginning
thejob
.
Cover
al¡
painted
surfaces
before
beginning
the
removal
procedure
.
As
an
aid
to
installation,
label
all
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
.
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
113-1
General
Coolingsystem,
draining
Cylinder
head
cover,
removing
Intake
manifold,
removing
Timing
chains,
uncoupling
Cylinder
head
assembly,
removing
WARNING
-
Allow
engine
to
cool
before
beginning
this
proce-
dure
.
General
1
.
Disconnect
negative
(-)
cable
from
battery
.
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
may
erase
fault
codees)
stored
in
control
module
memory
.
Check
for
fault
codes
using
special
BMW
diagnostic
equipment
.
NOTE-
The
battery
is
mounted
in
the
luggage
compartment
behind
the
right
side
trim
panel
.
2
.
Working
underneath
vehicle,
remove
front
exhaust
pipe
from
exhaust
manifold
.
See
Fig
.
1
.
3
.
Disconnect
vacuum
hose
fitting
from
brake
booster
on
rear
bulkhead
.
Plug
opening
in
booster
and
hose
end
.
CYLINDER
HEAD,
4-CYLINDER
Page 76 of 759
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
.