113-
1
8
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
CYLINDER
HEAD,
6-CYLINDER
Fig
.
46
.
Primary
chaintensioner
being
installed
.
Piston
cutout
must
engage
chain
rail
.
22
.
Install
intake
cam
cover
and
then
install
cylinder
head
cover
.
Check
for
correct
seating
of
half-moons
in
back
of
cylinder
head
cover
.
Use
a
small
amount
of
3-Bond
O
1209
orequivalent
seaiant
at
corners
of
half-moon
cut-
outs
.
23
.
Install
front
exhaust
pipes
to
manifolds
using
new
gas-
kets
and
nuts
.
Coat
manifold
studs
with
copper
paste
prior
to
installing
nuts
.
24
.
Installationof
remaining
parts
is
reverse
of
removal
.
Refill
cooling
system
as
described
in
170
Radiator
and
Cooling
System
.
Change
engine
oil
and
filter
as
de
scribed
in
020
Maintenance
Program
.
Check
adjust-
ment
of
accelerator
cable
.
Additional
tightening
torques
are
given
below
.
Reconnect
battery
last
.
25
.
Installationof
remaining
parts
is
reverse
of
removal,
noting
the
following
:
"
Make
sure
all
sealing
surfaces
are
clean
and
free
of
old
gasket
material
.
Insta¡¡
new
intake
manifold
gasket
.
"
Reinstall
harness
connectors
for
oil
pressure
switch
and
coolant
temperature
sensor
before
installing
in-
take
manifold
.
"
Refill
cooling
systemas
described
in
170
Radiator
and
Cooling
System
.
"
Change
engine
oil
and
filter
as
described
in
020
Main-
tenance
Program
.
"
If
necessary,
adjust
accelerator
cable
.
"
Reconnect
battery
last
.
CAUTION-
To
prevent
damaging
engine
electronic
systems,
be
sure
to
install
all
ground
wirespreviously
re-
moved,
including
the
ground
wires
at
the
cylinder
head
for
the
ignition
coils
.
Tightening
Torque
Tightening
Torques
"
Cylinder
head
cover
"
Coglant
drain
plug
to
cylinder
block
.
.
25
Nm
(18
ft-Ib)
to
cylinder
head(M6
screws)
.
.
.....
10
Nm
(89
in-lb)
"
Intake
manifold
to
cylinder
head
.
...
.
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)
119-2
LUBRICATION
SYSTEM
NOTE-
Component
Location
If
the
light
does
not
go
out,
thewiring
to
theswitch
is"
Oil
pressure
switch
most
likely
grounded
somewhere
between
the
switch
all
engines
.......
...
.
..
......
ora
oil
filter
housing
terminal
and
the
warning
light
.
Sea
Electrical
Wiring
Diagrams
atrearof
manual
for
electrical
schematics
.
CAUTION-
Some
oil
may
drain
out
as
the
oil
pressure
switch
is
removed
.
Use
a
rag
to
soak
up
any
spills
.
2
.
Install
pressure
gauge
in
place
of
switch
.
3
.
With
gauge
instalied,
start
engine
and
allow
to
reach
operating
temperature
.
Check
oil
pressureboth
cold
and
hot
.
NOTE-
For
the
most
accurate
test
results,
the
engine
oil
(and
filter)
shouldbe
newand
of
the
correct
grade
.
Oil
Pressure
"
¡dle
(mínimum)
..
.
.
..............
.
.
0
.5
bar
(7psi)
"
Regulated
pressure
(elevated
engine
speed)
4-cylinder
engines
..
......
4
.3
±
0
.2
bar
(63
t3
psi)
6-cylinder
engines
.
.
.............
.
4
.0
bar
(59
psi)
4
.
Remove
pressure
gauge
and
reinstall
pressure
switch
.
If
testing
shows
low
oil
pressure,
one
or
more
of
the
follow-
ing
conditions
may
be
indicated
:
OIL
PAN
"
Worn
or
faulty
oii
pump
.
"
Worn
or
faulty
engine
bearings
The
oil
pancan
be
removed
with
the
engine
instalied,
al-
Severe
engine
wear
.
though
specíal
enginesupport
equipment
will
be
needed
.
Al¡
of
these
conditionsindicate
the
need
for
major
repairs
.
Oil
pressure
warning
system,
testing
When
the
ignition
is
tumed
ora,
the
oil
pressure
warning
light
comes
ora
.
When
the
engine
ís
started
and
the
oil
pressure
ris-
es
slightly,
the
oil
pressure
switch
opens
and
thewarning
light
goes
out
.
Make
sure
the
oil
leve¡
is
correct
before
making
tests
.
1
.
Turra
ignition
switch
ora
.
"
Warning
light
ora
instrument
panel
must
light
up
.
2
.
Remove
connector
from
oil
pressure
switch
.
"
Warning
light
ora
instrument
panel
must
go
out
.
OIL
PAN
3
.
If
warning
light
does
not
light
when
ignition
is
ora,
re-
move
connector
from
oil
pressure
switch
anduse
a
jumper
wire
to
ground
connector
terminal
to
a
clean
metal
surface
.
NOTE
-
If
the
warning
light
comes
ora,
check
the
switch
as
de-
scríbed
in
the
nextstep
.
If
the
warning
light
does
not
come
ora,
thewiring
to
the
instrument
cluster
or
to
the
light
itself
isfaulty
.
4
.
To
test
switch,
connect
ara
ohmmeter
between
terminal
in
switch
body
and
ground
.
With
engine
off,
these
should
be
continuity
.
With
engine
running,
oil
pressure
should
opera
switch
and
there
should
beno
continuity
Replace
a
faulty
switch
.
WARNING
-
Keep
in
mind
that
low
oil
pressure
may
be
prevent-
ing
the
switch
from
tuming
the
light
out
.
If
the
light
remains
ora
while
the
engine
is
running,
check
the
oil
pressure
asdescribed
earlier
.
Do
not
drive
the
car
until
the
problem
is
corrected
.
Theengine
may
be
severely
damaged
.
Oil
pan,
removing
and
installing
(4-cylinder
engines)
1
.
Raise
car
arad
place
securely
ora
jackstands
.
2
.
Remove
splash
shíeld(s)
from
under
engine,
where
ap-
plicable
.
3
.
Drain
engine
oil
as
described
in
020
Maintenance
Pro-
gram
.
4
.
Disconnect
vacuum
hose
adapter
from
vacuum
brake
booster
at
rear
of
engine
compartment
.
5
.
Remove
oil
dipstick
guide
tube
mounting
nut
and
pull
guide
tube
from
oil
pan
.
See
Fig
.
2
.
120-2
IGNITION
SYSTEM
Fig
.1
.
Ignition
characteristic
map
.
Disabling
Ignition
System
WARNING
-
The
ignition
system
is
a
high-energy
system
operat-
ing
in
a
dangerous
voltage
range
that
couldprove
to
be
fatal
if
exposed
terminals
or
live
parts
are
con-
tacted
.
Use
extreme
caution
when
working
on
a
car
with
the
ignition
on
or
the
engine
running
.
The
ignition
system
operates
in
a
lethal
voltage
range
and
should
therefore
be
disabied
any
time
senrice
or
repair
work
is
being
doneon
the
engine
that
requires
the
ignition
to
be
switched
on
.
The
engine
management
system
can
be
disabled
byremov-
ingthe
main
relay
.
The
relay
is
located
in
the
power
distribution
box
in
the
left
rear
of
the
engine
compartment
.
See
Fig
.
2
.
0013134
Fig
.
2
.
Maínsystem
relay
(arrow)
in
power
distribution
box
(left
rear
of
engine
compartment)
.
GENERAL
WARNING
-
"
Do
not
touch
or
disconnect
any
of
the
high
ten-
sion
cables
at
the
cotls
orspark
plugs
while
the
engine
ts
running
orbeingcranked
by
the
starter
.
Fatalvoltages
are
present
.
"
Before
operating
the
starter
without
starting
the
engine
(for
example
when
making
a
compression
test)
always
disable
the
ignition
.
CAUTION-
"
Prior
to
disconnecting
the
battery,
read
the
bat-tery
disconnection
cautions
gtven
at
the
front
of
thts
manual
on
page
viti
.
"
Do
not
attempt
to
disable
the
ignition
by
either
re-
moving
the
cotl
from
the
spark
plugs
(6-cylinder
engines)
or
disconnecting
the
coll
wires
from
the
plugs
(4-cylinder
engines)
.
"
Connect
or
disconnect
ignition
system
wires,
multiple
connectors,
and
ignition
test
equipment
leads
only
while
the
ignitionis
off
.
Switch
multtm-
eter
functions
or
measurement
ranges
onty
with
the
test
probes
disconnected
.
"
Do
not
disconnect
the
battery
while
the
engine
ts
running
.
"
Many
of
the
tests
of
ignition
system
components
require
the
use
of
high-impedance
test
equip-
ment
to
prevent
damage
to
the
electrical
compo-
nents
.
A
high
impedance
digital
multimeter
should
be
used
for
all
voltage
and
resistance
tests
.
AnLED
test
light
shouldbe
used
in
place
of
an
incandescent-type
test
lamp
.
"In
general,
make
test
connections
only
as
speci-fied
by
BMW,
as
described
inthis
manual,
or
as
described
by
the
instrumenta
manufacturer
.
120-
4
IGNITION
SYSTEM
2
.
Check
for
battery
voltage
o
cofs
.
If
voltage
is
not
Table
b
.
Ignition
Coil
Resistance
present,
check
wire
between
terminal
15
and
ignition
(M42
Engine)
switch
.
See
Electrical
Wiring
Diagrams
.
"
On
M42
engine,
connect
digital
multimeter
between
ter-
minal
15(+)
in
each
harness
connector
and
ground
.
See
Fig
.
4
.
"
On
M44
engine,
connect
voltmeter
between
terminal
2
(15+)
in
connector
and
ground
.
Turn
ignition
on
and
check
for
voltage
.
See
Fig
.
5
.
3
.
Turn
ignition
off
.
0
4a15
Fig
.
4
.
Ignition
coil
harness
connector
terminal
identification
for
M42
engine
.
Fig
.
5
.
Ignition
coil
harness
connector
terminal
identification
for
M44
engine
.
CAUTION-
The
wiring
to
the
coil(via
the
ignition
switch
15+)
is
not
fuse
protected
.
Use
care
when
testing
thiscircuit
.
4
.
Use
a
digital
multimeter
totest
coil
primary
resistance
.
"
On
M42
engine,
use
Table
b
asa
guide
to
check
coil
resistance
.
Make
checks
at
each
harness
connector
.
"
On
M44
engine,
use
Table,c
as
a
guide
to
check
coil
primary
resistance
.
5
.
Inspect
coil
housing
for
hairline
cracks
or
leaking
cast-
ing
material
.
See
Fig
.
7
.
A
leaky
ignition
coil
may
indi-
11502
cate
a
faulty
ECM
(engine
control
module)
.
Check
the
ECM
before
installing
a
new
coil
.
Fig
.
6
.
Ignition
coil
harnessconnector
terminal
identification
for
6-
cylinder
engine
.
IGNITION
SYSTEM
SERVICE
11502
Terminals
Resistance
(refer
to
Fig
.
4
.)
Coil
primary
1
(-)
and
15
(+)
10
.4-0
.8
ohms
Coil
secondary
N
.A
.
N
.A
.
Table
c
.
Ignition
Coil
Resistance
(M44
Engine)
Terminais
Resistance
(referto
Fig
.
5
.)
Coil
#1
primary
1
(-)
and
2
(+)
0
.4-0
.8
ohms
Coil
#2
primary
6
(-)
and2
(+)
0
.4-0
.8
ohms
Coil
#3
primary
7
(-)
and
2
(+)
0
.4-0
.8
ohms
Coil
#4
primary
5
(-)
and2
(+)
0
.4-0
.8
ohms
Coil
secondary
N
.A
.
N
.A
.
NOTE-
If
a
single
coilís
faulty
on
M44
engines,
the
complete
coil
pack
will
have
to
be
replaced
.
Ignition
coil,
testing
and
replacing
(6-cylinder
engine)
CAUTION-
Use
a
digital
multimeter
for
the
following
tests
.
1.
Remove
plastic
enginecovers
from
top
of
engine
by
prying
off
nut
covers
and
removingcover
mounting
nuts
.
See
113
Cylinder
HeadRemoval
and
Installa-
tion
.
2
.
Disconnect
harnessconnectorfromcof
.
Connect
mul-
timeter
between
terminal
15
(+)
in
connector
and
ground
.
See
Fig
.
6
.
3
.
Turn
ignition
on
and
check
for
batteryvoltage
.
"
If
batteryvoltage
is
not
present,
check
wire
between
terminal
15
and
ignition
switch
.
See
Electrical
Wiring
Diagrams
.
"mozo
CAUTION
-
The
wiring
to
termina¡
15
(+)
of
the
coil(vía
the
ig-
nition
switch)
is
not
fuse
protected
.
Use
care
when
testíng
thiscircuit
.
4
.
Turn
ignition
off
.
5
.
Use
a
multimeter
to
test
coil
primary
resistanceat
coil
terminals
.
See
Table
d
.
Table
d
.
Ignition
Coil
Resistance
(6-cylinder
Engine)
Terminals
Resistance
(referto
Fig
.
4
.)
Coil
primary
1
1
(-)
and
15
(+)
X
0
.4-0
.8
ohms
Coil
secondary
l
N
.A
.
N
.A
.
6
.
Remove
coil
and
inspect
coil
housing
for
hairline
cracks
or
leaking
casting
material
.
See
Fig
.
7
.
A
leaky
ignition
coil
may
indícate
a
faulty
engine
control
module
(ECM)
.
Check
ECM
before
installing
a
new
coil
.
811004
Fig
.
7
.
Ignition
coil
being
removed
on
6-cylinder
engine
(M52
engine
shown)
.
CA
UTION-
"
Note
location
of
coil
ground
straps
before
coilre-
moval
;
reinstallin
the
same
location
.
"
When
replacing
ignition
coils,
ensure
that
the
re-
placement
coil(s)
are
from
the
same
manufactur-
er
containing
the
same
partlcode
numbers
.
If
individual
coils
with
the
correct
specifications
are
not
available,
all
coils
should
be
replaced
.
IGNITION
SYSTEM
120-
5
Crankshaft
Position/rpm
Sensor
If
the
engine
control
module
(ECM)
does
not
receive
a
crankshaft
position
signal
during
cranking,
the
engine
will
not
start
.
On
1992-1995(pre-OBD
II)
cars,
the
crankshaft
posi-
tion/rpm
sensor
is
mounted
on
the
front
engine
cover
and
reads
the
toothed
vibration
dampener
wheel
.
See
Fig
.
8
.
Fig
.
8
.
Crankshaft
position/rpm
sensor
mounted
at
front
of
engine
on
1992-1995
cars
.
(arrow)
.
On
1996
and
latee
cars
(OBD
II
compliant),
the
crankshaft
position/rpm
sensor
is
mounted
in
the
left
rear
side
of
the
cyl-
inderblock
.
The
sensor
reads
a
toothed
wheel
mounted
to
the
end
of
the
crankshaft
.
See
Fig
.
9
.
Fig
.
9
.
Crankshaft
position/rpm
sensor
toothed
wheel
mounted
to
rear
of
crankshaft
OBD
II
compliant
cars
.
The
sensor
is
mounted
in
the
left
rear
side
of
the
cylinder
block
.
IGNITION
SYSTEM
SERVICE
120-8
IGNITION
SYSTEM
1
1
.0
GN
1
.0
Gl
.0
GN
I
Ign
coil
1
.0
GN
.
Tti
%ti
r,
_%ti
_
_
ice_
I
25
52
5524
51
54
56
I
Power
input
power
input
t
U
Engine
Control
Module
(Bosch
DME
Ml
.7)
II
Powerinput
Mainrelaycontrol
I
15
42
43
16442868
67
34
6
26
27
1
-----
__
V
_
--
_
~
8K
.35
BK
.35
13,1
1
.35
YE
1
.35
BK35
VE
.35
3
cyl
.1
1
11
E
S
2
1
.0
BR
2
.5
BR
Ign
.
coil
cyl
.
3
II
Ign
.
coil
Ign
.
coil
3
cyI
.
2
1
Y
_
Y
2
k
3
cyl
.
4
IGNITION
SYSTEM
SCHEMATICS
Battery
voltage
in
run
or
start
(
vía
ignition
switchterminal
15)
WIRING
COLOR
CODE
4
.0
GN
1
.0
BR'V
.
Camshaft
Knock
Sensor
Knock
Sensor
Position
(cyl
.1-2)
(cyl
.3-4)
Sensor
Fig
.
13
.
Bosch
DME
M1
.7
ignition
system
circuit
for
M42
engine
.
Ground
(RH
rearof
engine
compartment,
rear
of
shock
tower)
N[INS
Crankshaftlrpm
Position
Sensor
Battery
voltage
in
run
or
start
(vía
main
relay
terminal
87)
Ground
(RH
rearof
engine
compartment,
rearof
shock
tower)
5GN
BK
-
BLACK
BR
"
BROWN
RD
-
RED
YL-
YELLOW
GN
-
GREEN
BL
-
BLUE
VI
-
VIOLET
GY
-
GREY
WT
-
WHITE
PK
-
PINK
Warning
:
Lethal
voltagepresent
Battery
voltage
at
all
times
to
Main
relay
(terminal
85)
'Y
Y
---------------------
0013087
^1
.5WT
^1
.5RD
^1
.5YL
^1
.5BL
r
--__
____-
__-_
___-_
-___-_____--__--
-____-___
____-
i
26
g
5022
23
54
5
I
Power
input
power
input
I
Engine
Control
Module
(Bosch
DME
M5
.2)
I
I
grounds
I
P
owerinput
Main
relay
control
I
70
40
71
21
2078
34
55
626
27
----------------------
-
---------
-
--
-
------------
-
-----------
.,
v
1
1
.1
v
`
1
35BK
35BK
2
(
1Y
¡3
194
Knock
Sensor
Knock
Sensor
(cyl
.1-2)
(cyl
.3-4)
Frommain
relay
terminal
87
(battery
voltage
in
run
or
start
Battery
voltage
in
run
or
start
(
via
ignition
switch
Warnin
terminal
15)
Lethal
óltage
WIRING
present
COLOR
CODE
2
.5
GN
'
1
.0
YL
/
1
.0
BL
/
1
.0
RDNJT
.35
BK
/
/
.35
BK
Camshaft
Position
Sensor
-_
Fig
.
14
.
Bosch
DME
M5
.2
ignition
system
circuit
for
M44
engine
.
Ground
(RH
rear
of
engine
compartment,
rearof
shock
tower)
Crankshaftirpm
Position
Sensor
IGNITION
SYSTEM
120-9
Batteryvoltage
Battery
voltage
in
run
or
start
in
run
or
start
(via
main
relay
(
via
ignition
switch
terminal
87)
terminal
15)
BK
-
BLACX
BR
-
BROWN
RD
-
RED
YL
-
YELLOW
GN
-
GREEN
BL
-
BLUE
VI
-
VIOLET
GY
-
GREY
WT
-
WHITE
PK
-
PINK
Battery
voltage
at
all
times
to
Main
relay
(terminal
85)
Ground
(RH
rear
of
engine
compartment,
rearof
shock
tower)
0012721
lGNITION
SYSTEM
SCHEMATlCS
120-10
IGNITION
SYSTEM
Ground
(rear
of
engine
compartment,
rear
of
passenger
side
shock
tower)
.!
BK
Camshaft
Position
Sensor
IGNITION
SYSTEM
SCHEMATICS
Batteryvoltage
in
run
or
start
(
via
ignition
switch
terminal
15)
---------------------------------------------------------
55
S5154
i
power
input
Power
input
1
DME
Control
Module(Bosch
DME
M3
.1)
Ground
-
(RHrear
of
enginecompartment,
rearof
passenger
side
shock
tower)
Fig
.
15
.
Bosch
DME
M3
.1
usedon1992
M50
engines(without
VANOS)
.
.EBK
Crankshaftlrpm
Position
Sensor
5GN
1.0
RD
Ground
(RH
rearof
enginecompartment,
rear
of
passenger
side
shock
tower)
WIRING
COLOR
CODE
BK
-
BLACK
BR
-
BROWN
RD
-
RED
YL
-
YELLOWGN
-
GREEN
BL
-
BLUE
VI-
VIOLET
GY
"
GREY
WT
"
WHITE
PK
-
PINK
Batteryvoltage
in
run
or
start
(
via
main
relay
Battery
voltage
terminal
87)
in
run
or
start
(via
ignition
switch
terminal
15)
11508
1
grounds
Main
rela
control
P
ower
Input
Y
I
-
34
---"--
6
26
27
1
Battery
voltage
at
all
times
to
Main
relay
(terminal
85)