1994 BMW M3 oil temperature
[x] Cancel search: oil temperaturePage 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 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 70 of 759
113-4
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
20
.
Disconnect
main
engine
wiring
harness
connector
.
La-
bel
and
disconnect
harness
connectors
for
crankshaft
and
camshaft
sensors
.
See
Fig
.
8
.
0012504
Fig
..
Crankcase
vent
valve
(A),
camshaft
and
crankshaft
sensor
harness
connectors
(B),
locating
bushings
(C),
main
engine
wiring
harnessconnector
(D)
.
M44
engine
shown
.
NOTE-
Early
engines
do
not
havea
maín
disconnect
at
the
lower
intake
manifold
harness
.
lf
necessary,
remove
the
cable
ducting
bolts
and
set
harness
ducting
aside
.
21
.
Remové
lower
section
of
intake
manifold
.
"
Remove
Y
shaped
supportbracket
from
underside
of
manifold
.
(See
Fig
.
6
.)
"
Unbolt
support
brackets
from
alternator
and
starter
.
"
Remove
nuts
holding
manifold
to
cylinder
head
and
pull
manifold
back
until
harness
connectors
for
oil
pressure
switch
and
coolant
temperature
sensorare
accessible
.
Label
and
disconnect
connectors,
then
re-
move
manifold
and
set
aside
.
Timing
chains,
uncoupling
26
.
Lock
crankshaft
in
TDC
position
by
insertíng
BMW
spe-
22
.
On
M42
engines,
remove
thermostat
housing
from
up-
cial
tool
no
.
11
2
300
through
bore
and
into
hole
infly-
per
timing
chaincover
.
wheel
or
driveplate
.
See
Fig
.
11
.
23
.
On
late
M44
engines
(January
1997
and
later),
remove
NOTE-
secondary
air
injection
check-valve
from
front
of
engine
"
If
necessary,
remove
plug
from
locating
bore
in
lower
and
lay
aside
.
edge
of
bell
housing
to
insert
locking
tool
.
24
.
Remove
cylinder
identification
sensor
from
upper
tim-
ing
chaincover
.
Remove
upper
timing
chaincover
.
See
Fig
.
9
.
25
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
See
Fig
.
10
.
CYLINDER
HEAD,
4-CYLINDER
Fig
.
9
.
Upper
timing
chain
cover
bolts
(arrows)
.
Remove
secondary
air
injection
check
valve
fromhose
(A)
on
M44
engine
.
Re-
move
cylinder
identification
sensor
from
chaincover
(B)
.
0011998
Fig
.
10
.
Engine
set
to
approximate
TDC
.
Cylinder
no
.
1
camshaft
lobes
face
in
and
arrows
on
sprockets
poínt
up
(arrows)
.
"
Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotate
the
crankshaft
.
27
.
Lock
camshafts
at
TDC
by
mounting
BMW
specíal
tool
no
.
113
240
over
square
ends
of
camshafts
.
See
Fig
.
12
.
NOTE-
Check
that
tool
is
squarely
seated
on
cylinder
head
gasket
surface
.
If
necessary,
rotate
camshafts
slightly
using
an
open-end
wrench
at
hex
oncamshafts
.
Page 75 of 759
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
Page 84 of 759
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)
Page 110 of 759
117-
1
4
CAMSHAFT
TIMING
CHAIN
22
.
Installation
of
remaining
parts
is
reverse
of
removal,
When
theengine
is
running,
the
piston
housing
is
supplied
noting
the
following
:
with
pressurized
engine
oil
.
At
idie,
the
solenoid
isin
the
off
"
When
installing
thermostat,
make
sure
arrow
or
vent
position
(de-energized)
and
valve
timing
is
maintained
in
the
hole
faces
up,
if
applicable
.
normal
position
:
When
the
solenoid
is
energized,
the
gear
cup
"
Refill
cooling
systemas
described
in
170
Radiator
piston
moves
forward
to
advance
the
camshaftby
a
maximum
and
Coming
System
.
of
12
.5
.
"
Install
oil
pan
as
described
in
119
Lubrication
Sys-
tem
.
"
Fill
engine
with
oil
and
install
a
new
oil
filter
as
de-
scribed
in
020
Maintenance
Program
.
"
Insta¡¡
ground
wires
at
cylinder
head
cover
mounting
studs
and
at
front
of
cylinder
head
and
thermostat
housing,
where
applicable
.
VANOS
system
operation,
testing
Tightening
Torques
There
are3
special
tools
required
to
check
VANOS
opera-
"
Coolant
drain
plugto
cylinder
block
.
.
25
Nm
(18
ft-Ib)
tion
;
an
electricaltest
lead
(BMW
special
tool
no
.
12
6
410),
an
"
Radiator
cooling
fan
to
coolant
pump
.
40
Nm
(30
ft-Ib)
air
line
fitting
(BMW
special
tool
no
.
11
3
450),
and
a
crank-
"
Radiator
drain
screw
to
radiator
...
.
2
.5
Nm
(22
in-Ib)
shaft
TDC
locking
tool
(BMW
special
tool
no
.
112
300)
.
"
Upper
timing
chaincover
to
cylinder
head
The
test
leal
is
used
to
power
the
solenoid,
simulating
the
M6
nut
...
.....
.............
..
.
10
Nm
(89
in-lb)
ground
signal
from
the
DME
control
unit
.
The
air
line
fitting
M8
bolt
.....
....
.
.
.............
22
Nm
(17
ft-Ib)
takes
the
place
of
the
oil
supply
line
fitting
to
simulate
oil
Ares-
"
VANOS
control
unit
to
cylinder
head
sure
.
The
locking
tool
positions
and
locks
the
crankshaft
at
M6
nut
.........
..
..
.
..........
10
Nm
(89
in-lb)
TDC,
cylinder
no
.
l.
M8
bolt
........
...
.............
22
Nm
(17
ft-Ib)
"
VANOS
oil
supply
pipe
to
VANOS
control
unit
1
.
Remove
alternator
cooling
air
duct
.
banjo
bolt
.......
..
..
.
..........
32
Nm
(24
ft-Ib)
VANOS
(VARIABLE
VALVE
TIMING)
3
.
Remove
top
plastic
enginecovers
.
Disconnect
ignition
coil
harness
connectors
fromcofs
.
Remove
ignition
1993
and
later
6-cylinder
engines
are
equipped
with
a
vari-
coils
.
able
valve
timing
system
called
VANOS
.
This
system
is
con-
trolled
by
the
engine
management
system
and
dynamically
4
.
Remove
cylinder
head
cover
mounting
bolts
and
re-
adjusts
intake
camshaft
timing
based
on
engine
load,
engine
move
cylinder
head
cover
.
Unclip
andremove
oil
baffle
speed
and
engine
temperature
.
cover
from
above
intake
camshaft
.
See
113
Cylinder
Head
Removal
and
installation
.
The
main
components
of
the
VANOS
system
are
the
control
unit
with
piston
housing
and
integral
spool
valve,
and
the
mod-
ified
intake
camshaft
.
See
Fig
.
35
.
VANOS
(VARIABLE
VA
LVE
TIMING)
Fig
.
35
.
VANOS
control
unit
with
modified
intake
camshaft
.
B11001
WARNING
-
Special
BMW
service
tools
are
required
to
check
and
repair
the
VANOS
System
.
Read
theproce-
dures
through
before
beginning
the
job
.
2
.
Disconnect
crankcase
ventilation
hose
fitting
from
cyl-
inder
head
cover
.
NOTE-
Note
the
arrangement
of
the
cylinder
head
cover
bolt
insulators
and
gaskets
during
removal
.
5
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
See
Fig
.
20
.
6
.
Set
engine
to
TDC
by
aligning
"0/T"
mark
(0°TDC)on
front
vibration
damper
withcast
boss
on
lower
timing
chain
cover
.
See
Fig
.
21
.
7
.
Lock
crankshaft
in
position
by
inserting
BMW
special
tool
no
.
11
2
300
through
transmission
bellhousing
and
into
hole
in
flywheelor
driveplate
.
See
Fig
.
36
.
NOTE-
Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotatethe
crankshaft
.
Page 116 of 759
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
.
Page 125 of 759
GENERAL
.
........
.
...........
.
.
.
.
.
.
.
120-1
Camshaft
Position
(CMP)
Sensor
....
.
.
.
...
120-6
Disabling
Ignition
System
.
.
.
.
.....
.
.
.
.
.
.
.
120-2
Camshaft
position
(CMP)
sensor,
replacing
Warnings
and
Cautions
.
.
.
.
.
.
.....
.
.
.
.
.
.
.
120-2
(4-cylinder
engine)
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
...
120-6
Camshaft
position
(CMP)
sensor,
replacing
IGNITION
SYSTEM
DIAGNOSTICS
.
.
.
.
.
.
120-3
(6-cylinder
engine)
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
120-7
Basic
Troubleshooting
Principles
...
.
.
.
.
.
.
.
120-3
Knock
sensors,
replacing
.
.
...
.
.
.
.
.
.
.
.
.
.
.
.
120-7
Ignition
Firing
Order
.....
.
...
.
.
.
.....
.
.
.
.120-7
IGNITION
SYSTEM
SERVICE
.
.........
.
120-3
Checking
for
Spark
..
.
.
.
.
.
.
.
.
.
.......
.
.
.
120-3
Ignition
coil,
testing
and
replacing
(4-cylinder
engine)
.
.
.
.
.
.
.
.
.
.
.........
.
120-3
Ignition
coil,
testing
and
replacing
(6-cylinder
engine)
.........
.
..........
120-4
Crankshaft
Positionlrpm
Sensor
.......
.
...
120-5
Crankshaft
position/rpm
sensor,
testing
and
replacing
(front
mounted)
.........
.
.
.
.
.
.
120-6
Crankshaft
position/rpm
sensor,replacing
(rear
mounted)
.....
.
.....
.
.....
.
.
.
.
.
.
120-6
GENERAL
Troubleshooting
and
testing
of
the
engine
management
system
should
be
carried
out
using
the
BMW
specialized
ser
This
repair
group
covers
repair
andcomponent
replace-
vice
tester
(scan
tool)
.
ment
information
for
the
ignition
system
.
All
engines
use
a
distributorless
ignition
system
with
indívid-
ual
ignitioncoils
for
each
cylinder
.
There
is
no
distributor
cap
NOTE-
or
ignition
rotor
.
Each
coil
can
be
selectively
controlled
by
the
"
Spark
plug
replacement
is
covered
in
020
Mainte-
engine
control
module
on
a
cylinder-by-cylinder
basis
.
On
later
nance
Program
.
systems,
knock
sensors
are
used
to
monitor
and
control
igni-
"
For
fuel
related
troubleshooting
and
testing,
see
130
tion
knock
(ping)
and
adjusttiming
accordingly
.
Fuel
lnjection
.
Ignition
timing
is
electronically
controlled
and
not
adjust-
All
engines
covered
by
this
manual
use
an
advanced
en-
able
.
The
engine
control
module
(ECM)
usesengine
load,
en-
gine
management
system
.
The
engine
management
system
gine
speed,
coolant
temperature,
and
intake
air
temperature
incorporates
on-board
diagnostics,
fuel
injection,
ignition
and
as
the
basic
inputs
for
timing
control
.
Knock
detection
is
also
other
advanced
engine
control
functions
.
an
input
to
the
control
module,
where
applicable
.
Table
a
.
Engine
Management
System
Variants
Engine
code
1
System
4-cylinder
M42
(1.8
I)
Bosch
DME
Ml
.7
M44
(1
.9
I)
Bosch
DME
M5
.2
(OBD
II)
6-cylinder
M50
1992
(2.5
I)
Bosch
DME
M8
.1
1993-1995
(2
.5
I)
Bosch
DME
M33
.1
M52
1996-1998
(2.8
I)
Siemens
MS
41
.1
(OBD
II)
1998
(2
.5
I)
Siemens
MS
41
.1
(013D
11)
S50US
(3.0
I)
Bosch
DME
M3
.3.1
S52US
(3.2
I)
Siemens
MS
41
.1
(OBD
II)
120
Ignition
System
IGNITION
SYSTEM
120-1
IGNITION
SYSTEM
SCHEMATICS
...
.
.
.
.120-7
TABLES
a
.
Engine
Management
System
Variants
......
120-1
b
.
Ignition
Coil
Resistance
(M42
engine)
......
120-4
c
.
Ignition
Coil
Resistance
(M44
engine)
......
120-4
d
.
Ignition
Coil
Resistance
(6-cylinder
engine)
..
.
.
.
.
.
.
.
.
.
.
.
.....
.
..
120-5
NOTE-
All
engines
coveredby
this
manual,
with
theexception
of
the
1992
M50,
incorporate
knocksensors
as
part
of
the
engine
management
system
.
The
initial
ignition
point
is
determined
by
the
crankshaft
po-
sition/rpm
sensor
during
cranking
.
Once
the
engine
is
run-
ning,
timing
is
continually
adjusted
based
on
operating
conditions
.
A
characteristic
ignition
map
is
shown
in
Fig
.
1
.
A
map
similar
to
the
one
shown
is
digitally
stored
in
the
engine
control
module
.
GENERAL