cooling BMW 318i 1997 E36 User Guide

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
.

110-2



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
.

14
.
Unbolt
power
steering
fluid
reservoir
from
íts
mounting
bracket
.
Use
stiff
wire
to
hang
reservoir
to
one
side
.
Do
not
disconnect
fluid
lines
.

15
.
Remove
power
steering
pump
drive
belt
and
remove
pump
from
its
mounting
bracket
.
Use
stiff
wire
to
hang
pump
from
body
.

16
.
On
cars
with
automatic
transmission
remove
front
and
rear
brackets
holding
automatic
transmission
cooler
linesto
engine
.

17
.
Remove
A/C
compressor
from
its
mounting
bracket
without
disconnecting
any
refrigerantlines
.
See
Fig
.
5
.

ENGINE
REMOVAL
AND
INSTALLATION



110-
3

21
.
Remove
front
exhaust
pipefrom
exhaust
manifold
.
See

Fig
.
6
.

22
.
Install
an
engine
lifting
device
and
raise
engine
until
its

weight
is
supported
.
Remove
nuts
and
ground
strap

from
left
and
right
engine
mounts
.

0011967

Fig
.
6
.



Front
exhaustpipe
to
exhaust
mounting
nuts
(arrows),
as
viewed
from
below
on
4-cylinder
engine
.

23
.
Carefully
raíse
engine
out
of
car,
checking
for
any
wir-
ing
harnesses,
fuel
lines,
or
mechanical
parts
that
might
become
snagged
as
engine
is
removed
.

24
.
Installation
is
reverse
of
removal,
noting
the
following
:

"
Replace
all
gaskets,
O-rings
and
seals
.

"
Change
engine
oil
and
filter
and
check
al¡
other
fluid
levels
.
See020
Maintenance
Program
.
"
Refill
and
bleed
cooling
system
.
See
170
Radiator
and
Cooling
System
.

"
Insta¡¡
the
front
exhaust
pipes
using
new
gaskets
and

self-locking
nuts
.
Use
copper
pasteon
threads
.
See

180
Exhaust
System
.

Tightening
Torques

"
Coolant
drain
plug
to
cylinder
block
.
25
Nm
(18
ft-Ib)

Fig
.
5
.
A/
C
compressor
mounting
bolts
(arrows)
.



"
Engine
mount
to
subframe

M8
......:...
..
..
..
......,:..
22
Nm
(17
ft
-
1b)
,

18
.
Move
A/C
compressor
out
of
way
without
distorting
or



M10
.
...
.



..
...
.
.
...........
45
Nm
(33
ft'-Ib)

damaging
any
lines
.
Support
compressor
by
hanging
it



"
Intake
manifold
to
cylinder
head

from
chassis
using
stiff
wire
.



M7
.....
.
..
...
..
..
...........
15
Nm
(11
ft-Ib)
M8
...
.
.
.
..
..
...
..
...........
22
Nm
(16
ft-Ib)

19
.
Disconnect
wiring
from
starter
and
alternator
.
Move



`
"
Radiator
cooling
fan
to
coolant
pump40
Nm
(30
ft-Ib)

wiring
harness
out
of
way
.
See
121
Battery,
Starter,



"
Radiator
drain
screw
to
radiator
...
2
.5
Nm
(22
in-lb)

Alternator
.



"
Wiring
to
alternator
(M8
nut)
........
12
Nm
(9
ft-1b)

"
Wiring
to
starter

20
.
Remove
oil
dipstick
guide
tube
.
Note
O-ring
at
base
of



M6
nut
..
.
..
..
...
..
...........
.
:5
Nm
(44
in-lb)

tube
when
removing
.



M8
nut
..
.
..
..
...
..
............
12
Nm
(9
ft-Ib)

ENGINE
REMOVAL
AND
INSTALLATION

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

22
.
Move
A/C
compressor
out
of
the
way
without
distorting



26
.
Carefully
raise
engine
out
ofcar,
checking
for
any
wir-
or
damaging
any
lines
.
Support
compressor
by
hanging



ing,fuel
lines,
or
mechanical
parts
that
might
become
it
from
chassis
using
stiff
wire
.



snagged
as
engine
is
removed
.

23
.
Disconnect
wiring
from
starter
and
alternator
.
Move



27
.
Installation
is
reverse
of
removal,
noting
the
following
:
wiring
harness
out
of
the
way
.
See
121
Battery,
Start-
Replace
al¡
gaskets,
O-rings
and
seals
.
er,
Alternator
.



"
Change
engine
oil
and
filter
and
check
all
other
fluid

24
.
Remove
Fontexhaust
pipe
fromexhaust
manifold
.
See



levels
.
See
020
Maintenance
Program
.
"
Refill
and
bleed
cooling
system
.
See
170
Radiator
Fig
.
16
.



and
Cooling
System
.

"
Check
that
engine
drivebelts
properly
engage
the
pul-

ley
grooves
.

"
Install
the
Font
exhaust
pipesusing
new
gaskets
and
seif-locking
nuts
.
Use
copper
paste
on
threads
.
See
180
Exhaust
System
.

0012525

Fig
.
16
.
Front
exhaust
pipeto
exhaust
manifolds
mounting
nuts
on
6-

cylinder
engine
(arrows)
.

25
.
Install
an
engine
lifting
device
and
raise
engine
until
its

weight
is
supported
.
Remove
nuts
and
ground
strap

from
left
and
right
engine
mounts
.

ENGINE
REMOVAL
AND
INSTALLATION



110-
7

Tightening
Torques

"
Coolant
drain
plug
to
cylinder
block
.
25
Nm
(18
ft-Ib)
"
Engine
mount
to
subframe
M10
..
.
.
.
...
..............
..
.
45
Nm
(33
ft-Ib)

M8
..
..
.
..
................
...
22
Nm
(16
ft-Ib)

"
Intake
manifold
to
cylinder
head

M7
..
..
..
...
................
.
15
Nm
(11
ft-Ib)

M8
...
.
..
...
................
.
22
Nm
(16
ft-Ib)
"
Radiator
cooling
fan
to
coolant
pump40
Nm
(30
ft-Ib)

"
Radiator
drain
screw
to
radíator
...
2
.5
Nm
(22
in-lb)
"
Wiring
to
alternator
(M8
nut)
........
12
Nm
(9
ft-Ib)

"
Wiring
to
starter

M6
nut



.
..
...
..................
5
Nm
(44
in-lb)

M8
nut
.....
..
.
.
.
.
.............
12
Nm
(9
ft-Ib)

ENGINE
REMOVAL
AND
INSTALLATION

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

113-2



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

0011s6i



-

0Fig
.
1
.



Front
exhaust
pipe
to
exhaust
manifold
mountíng
nuts
(arrows)
.
-1



~~
0013023

4
.
Remove
air
filter
housing
complete
with
mass
air
flow



Fig
.
3
.



Coolant
hose
connection
beneath
intake
manifold
on
M42

sensor
and
attached
hoses
and
ducting
.
See
Fig
.
2
.



engine
(arrow)
.

0011969

Fig
.
2
.



Air
filter
housing/air
intake
connections
on
M44
engine
with
traction
control
.
Clamp
atthrottle
housing
(A)
;
mass
air
flow
sensor
connector
(B)
;
and
clips
at
upper
air
filter
housing
(C)
.

Coolingsystem,
draining

5
.
Draincoolant
from
engine
block
and
radiator
.
See
170

Radiator
and
Cooling
System
.

NOTE-

"
The
block
drain
is
on
the
exhaust
sideof
the
engine,
near
cylinder
no
.
4
.

6
.
Disconnect
hoses
from
coolant
flange/thermostat
hous-
ing
on
frontof
cylinder
head
.
Unbolt
thermostat
housing
from
cylinder
head
.

CYLINDER
HEAD,
4-CYLINDER

7
.
On
M42
engines,
disconnect
hose
from
coolant
pipe
on

left
side
of
engine
.
See
Fig
.
3
.

8
.
Disconnect
heater
hoses
from
coolant
flange
on
rear
of
cylinder
head
.

Cylinder
head
cover,
removing

9
.
Remove
ignition
coil
pack
from
rightstrut
tower
.
See

Fig
.
4
.

0011995
"
The
radiator
drain
plug
is
on
the
bottomof
the
radiator



Fig
.
4
.



Cylinder
head
cover
showing
location
of
engine
breather
hose
on
the
driver's
side
.
Remove
small
plastic
lock
clipto



(A),
wiring
harness
duct
(B),
and
ignition
coil
pack
(C)
.
M44
pull
radiator
drain
plug
out
completely
.



engine
shown
.
Cover
on
M42
engine
is
similar
.

10
.
Disconnect
engine
breather
hose
from
cylinder
head
cover
.

Fig
.
23
.
When
reinstalling
chain
tensioner
on
M44
engine,
old
oil
in
tensioner
piston
mustbe
expelled
bycompressing
piston
in
vise
.
When
compressing
piston,
only
compress
up
to
end
cir-
clip
(arrow)
.

21
.
Turn
engine
overby
hand
in
direction
of
rotation
at
least

two
fui¡
rotations
.
Reinstall
camshaft
and
crankshaft

locking
tools
to
check
engíne
timing
.
Remove
locking

tools
if
no
faults
are
found
.

22
.
Insta¡¡
upper
timingchain
cover
.

"
Install
gaskets
and
instan
cover
using
two
mounting



Tightening
Torque

bolts
.
Using
a
screwdriver,
lever
down
on
front
cover



"
Cylinder
head
cover
until
cover
gasket
surface
is
flush
with
cylinder
head



to
cylinder
head
(M6
screws)
.......
10
Nm
(89
in-lb)

gasket
surface
.
See
Fig
.
24
.
Tighten
two
bolis
.

"
Insta¡¡
and
tighten
remainder
of
bolis
.

23
.
Install
cylinder
head
cover
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-
9

0012507

Fig
.
24
.
Install
upper
timing
case
cover
with
two
bolis,
then
press

down
on
cover
so
that
top
surface
is
flush
withcylinder
head
(arrow)
.
Hold
cover
in
position
and
tighten
bolis
.

"
Clean
old
gasket
glue
from
sealing
surfaces
.
Usea

small
amount
of
3-Bond
®
1209
adhesive
or
equivalent

at
corners
of
half-moon
cut-outs
at
back
of
cylinder

head
.
See
Fig
.
25
.

NOTE-

OnM44
engines,
reptace
sea¡
for
oil
supply
tube
.
See
Fig
.
17
.)

Fig
.
25
.
Rear
of
cylinder
head
cover
showing
area
where
sealant
(ar-
rows)
should
be
applied
.
Inset
shows
cylinder
head
cover
mounting
bolt
and
insulator
assembly
:
M6
screw
(1),
rubber
damper
(2),
washer
(3)
.

24
.
Installation
of
remaining
parts
is
reverseofremoval,

noting
the
following
:

"
Make
sure
al¡
sealing
surfaces
are
clean
and
free
of
old

gasket
material
.
Install
new
intake
manifold
gasket
.

"
On
M44
engine
:
Replace
seals
above
and
below

crankcase
ventvalve
.

"
When
installing
lower
intake
manifold,
make
sure
hol-

low
locating
bushings
are
on
two
lower
studs
.

"
Reinstall
harness
connectors
for
oil
pressure
switch

and
coolant
temperature
sensor
before
installing
in-

take
manifold
.
Tighten
manifold
nuts
in
stages
.

"
Refill
cooling
system
as
described
in
170
Radiator

and
Cooling
System
.

"
Change
engine
oil
and
filter
as
described
in
020
Main-

tenance
Program
.

"
If
necessary,
adjust
accelerator
cable
.

"
Run
engine
at
approx
.
3,500
rpm
for
about
20
seconds

to
allow
hydraulic
chain
tensioner
to
fill
with
oil
.

"
Reconnect
battery
last
.

CYLINDER
HEAD,-CYLINDER

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
.