coils BMW 325i 1994 E36 User Guide

5
.
Pull
hydraulic
valve
adjuster
straight
out
of
cylinder

head
.
See
Fig
.
13
.

Fig
.
13
.
Remove
hydraulic
valve
adjuster
by
pulling
straight
out
ofcyl-
inder
head
(arrow)
.

6
.
Installation
is
reverse
of
removal
.
Be
sure
to
inspect

HVA
bore
in
the
cylinder
head
for
wear
or
scoring
.

Tightening
Torque

"
Cylinder
head
cover
to
cylinder
head/timing
chain
cover

M6
bolt
.........
..
..
...
........
10
Nm
(89
in-lb)

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

Hydraulic
cam
followers,

checking
and
replacing

(M42
and
al¡
6-cylinder
engines)

The
M42
engine
and
al¡
6-cylinder
engines
use
self-adjust-

ing
hydraulic
cam
followers
to
keep
the
valveclearances
with-

ina
limited
working
range
.
The
cam
followers
are
sealed
units

and
require
no
maintenance
.
See
Fig
.
14
.
.

Under
some
circumstances,
suchasa
cold
start,
the
cam

followers
may
become
noisy
.
Hydraulic
cam
follower
noise
is

usually
a
high-pitched
tapping
or
chattering
noise
.
In
most
in-

stances,
this
is
considered
normalas
long
as
the
noise
goes

away
in
a
fewminutes
(maximum
20
minutes)
.
lf
the
noise

does
not
go
away,
either
the
follower
is
faulty
or
the
oil
pres-

sure
to
the
follower
is
low
.
Hydraulic
cam
follower
replace-

ment
requires
that
the
camshaft
first
be
removed
.

NOTE-

Before
checking
valve
adjusters,
make
sure
engine
oil

ís
fresh
and
at
proper
level
.

CYLINDER
HEAD
AND
VALVETRAIN



116-
9

Fig
.
14
.
Section
view
of
camshaft
(A),
hydraulic
cam
follower
(B),
and
valvewith
conical
valvespring
(C)
usedon
M52
engine
.

1.
Run
engine
until
it
reachesnormal
operating
tempera-

ture
.

2
.
Turn
engine
off
and
remove
top
engine
covers,
ignition

coils,
and
cylinder
head
covers
.
See
113
Cylinder

Head
Removal
and
Installation
.

3
.
Use
a
plastic
or
wooden
stickto
press
down
on
top
of

cam
follower
.
See
Fig
.
15
.
If
there
is
any
noticeable

clearance,
the
follower
is
faulty
and
should
be
replaced
.

811107

Fig
.
15
.
Hydraulic
cam
follower
in
M52
enginebeing
checked
.
Note

that
camshaft
lobe
is
pointing
up
.

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING

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
.

117-
1
6



CAMSHAFT
TIMING
CHAIN

15
.
Remove
crankshaft
locking
tool
.
Remove
special
test

equipment
.
Insta¡¡
oil
supply
line
using
new
seals
and

reconnect
solenoid
connector
.
Remainder
of
installa-

tion
is
reverse
of
removal
.

Tightening
Torque

"
Cylinder
head
cover
to
cylinder
head
.
10
Nm
(89
in-lb)

"
VANOS
oil
supply
line
to
VANOS

control
unit
(banjo
bolt)



..
.........
32
Nm
(24
ft-Ib)

"
VANOS
solenoidlo
VANOS

control
unit
........
.
.
.
..
........
30
Nm
(22
ft-Ib)

VANOS
control
unit,
removing

Special
BMW
service
tools
are
required
lo
remove
and
in-

stall
the
VANOS
control
unit
.
Read
the
procedure
through
be-

forestarting
the
job
.

1
.
Remove
radiator
cooling
fan
shroud
and
cooling
fan
.

See
170
Radiator
and
Cooling
System
.

CAUTION-

Radiator
fan
has
left
hand
threads
.

2
.
Remove
top
plastic
engine
covers
.
Disconnect
ignition

coil
harness
connectors
from
coils
.
Remove
ignition

coils
.
Remove
cylinder
head
cover
.
Unclip
andremove

oil
baffle
cover
from
above
intake
camshaft
.See
113

Cylinder
Head
Removal
and
Installation
.

NOTE-

Make
note
of
the
mounting
bolt
insulator
arrangement
during
removal
of
the
cylinder
head
cover
.

3
.
Set
engine
lo
TDC
by
rotating
engine
in
normal
operat-

ing
direction
until
camshaft
lobes
at
cylinder
no
.
1
are

facing
each
other
and
"0/T"
mark
(0°TDC)
on
vibration

damper
lines
up
with
cast
boss
on
lower
timing
chain
cover
.
See
Fig
.
38
.

4
.
Lock
crankshaft
at
TDC
by
inserting
BMW
special
tool

no
.
11
2
300
through
transmission
bellhousing
and
finto

flywheel
or
drive
plate
.
Refer
to
Fig
.
36
given
earlier
.

NOTE-

Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotatethe
crankshaft
.

5
.
Remove
three
cylinder
head
cover
mounting
studs
from
rear
of
head
.
Lockcamshafts
at
TDC
bymounting

BMW
special
tool
no
.
11
3
240
at
ends
of
camshafts
.

Check
that
tool
is
squarely
seated
on
cylinder
head
gasket
surface
.
If
necessary,
rotate
camshafts
slightly
using
a24
mm
wrench
.
Refer
to
Fig
.
24
given
earlier
.

VANOS
(VARIABLE
VALVE
TIMING)

Fig
.
38
.
Camshafts
positioned
at
TDC-Cyl
.
No
.
1
cam
lobes
face
in
Note
0/T
mark
(0°TDC)
on
vibration
damper
alígned
with
boss
on
front
cover
.

CA
UTION-

Thecamshafts
mustbe
locked
in
the
TDC
position
using
the
specialservice
tool
or
an
equivalent
be-
fore
removing
the
timing
chain
.
Thearrows
on
the
sprockets
should
not
be
used
to
accurately
set
the
engine
to
TDC
The
special
tool
holds
the
cam-
shafts
parallel
to
each
other
and
perpendicular
to
the
valve
cover
gasket
surface
.

6
.
Disconnect
harness
connector
and
oil
line
fitting
from
bottom
of
VANOS
control
unit
.

NOTE-

Wrap
the
VANOS
oilfine
fitting
with
a
shop
rag
to
ab-
sorb
leaking
oil
.

7
.
Remove
two
access
plugs
from
VANOS
control
unit
in
frontof
exhaustcamshaft
sprocket
.
Loosen
4exhaustcamshaft
sprocket
mounting
bolts
but
do
not
remove

(Torx
El
0
socket)
.

NOTE-

Removal
of
the
access
plugs
allows
the
lower
exhaust
camshaft
sprocket
mounting
bolts
to
be
accessed
.

8
.
Depress
secondary
timing
chain
tensioner
and
lock
it
in
down
position
by
inserting
a
stiff
wire
into
rear
of
ten-
sioner
.
See
Fig
.
27
.

9
.
Remove
VANOS
control
unít
mounting
nuts
and
boltat

front
of
cylinder
head
.

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

IGNITION
SYSTEM
DIAGNOSTICS



IGNITION
SYSTEM
SERVICE

Poor
driveability
may
have
a
variety
of
causes
.
The
fault



On
4-cylinder
engines,
an
ignition
coil
pack
is
mounted
to

may
lie
with
the
ignition
system,
the
fuel
system,
parts
of
the



the
passenger
side
strut
tower
in
the
engine
compartment
.

emission
control
system,
or
a
combination
of
the
three
.
Be-



The
coil
pack
integrates
4
individual
coils
.

cause
of
these
interrelated
functions
and
their
effects
oneach

other,
it
is
often
difficult
to
know
where
to
begin
looking
for



On
6-cylinder
engines,
an
ignition
coil
is
located
directly

problems
.



above
each
spark
plug
.

For
this
reason,
effective
troubleshooting
should
alwaysbe-

gin
with
an
interrogation
of
the
On-Board
Diagnostic
(OBD)

system
.
The
OBD
system
detects
certain
emissions-related

engine
management
malfunctions
.
When
faults
are
detected,

the
OBD
system
stores
a
Diagnostic
Trouble
Code
(DTC)
in

the
system
ECM
.
In
addition,
the
Check
Enginewarning
light

will
come
on
if
an
emissions-related
fault
is
detected
.

Two
generations
of
OBD
areusedon
the
cars
coveredby

this
manual
.
See
100
Engine-General
for
OBD
information
.

On-Board
Diagnostics

"
1992-1995
models
............
...
.
..
...



OBD
I

"
1996
and
later
models
.........
.......
..
OBD
II

NOTE-

"
On
carswith
OBD
ti,
specialized
OBD
11
scan
tool

equipment
mustbeused
to
access
DTCs,
either
using

the
BMW
special
tool
or
a
`generic"
OBD
11
scan
tool
.

"
The
OBD
11
fault
memory
(including
an
illuminated

Check
Engine
light)
can
only
be
reset
using
the
spe-

cial
scan
tool
.
Removing
the
connector
from
the
ECM

or
dísconnecting
the
battery
will
not
erase
the
fault

memory
.

Basic
Troubleshooting
Principies

An
engine
that
starts
and
runs
indicates
the
ignition
system

is
fundamentally
working-delivering
voltage
toat
least
some

of
the
sparkplugs
.
A
hard-starting
or
poor-running
engine,

however,
may
indicate
ignition
coil
problems,
cracked
or
dete-

riorated
spark
plug
wires
(4-cylinder
engines
only),
and
worn

or
fouled
spark
plugs
.

WARNING
-

Inefficient
combustion
(richair/fuel
mixture)
can

cause
the
catalytic
converter
to
overheat
and
plug
.

An
overheated
catalytic
converter
can
also
bea
tire

hazard
.

Checking
for
Spark

IGNITION
SYSTEM



120-
3

WARNING
-

If
a
spark
test
is
done
incorrectly,
damage
to
theen-
gine
control
module
(ECM)
or
the
ignitioncoil(s)
may
result
.

Checking
for
spark
is
difficult
onengines
with
distributorless

ignition
systems
.

Try
Rmovng
the
plugs
and
inspecting
for
differences
be-

tween
them
.
A
poor-firing
plug
may
be
wet
with
fuel
and/or

black
and
sooty,
butnot
always
.
If
a
coil
is
not
operating,
the

engine
management
system
will
electrically
disable
the
fuel
injectorto
that
cylinder
.
The
key
is
to
look
for
differences
be-

tween
cylinders
.

Ignition
coil,
testing
and
replacing

(4-cylinder
engine)

1.
Disconnect
mainharness
connector
from
coils
:

"
On
M42
engine,
remove
plastic
covering
from
coils
and

disconnect
individual
harness
connectors
.

"
On
M44
engine,
disconnect
main
harness
connectorat

end
of
coil
pack
.
See
Fig
.
3
.

Fig
.
3
.



Ignition
coil
pack
for
M44
engine
(arrow)
.
Coil
harness
con-

nector
shown
at1
.

IGNITION
SYSTEM
SERVICE

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

130-
6



FUEL
INJECTION

Warnings
and
Cautions

For
personal
safety,
as
well
as
the
protection
of
sensitive

electronic
components,
the
following
warnings
and
cautions

should
be
adhered
to
when
working
on
the
engine
manage-

ment
system
.

GENERAL
WARNING
-

"
The
ignition
system
produces
high
voltages
that

can
be
fatal
.
Avoid
contact
with
exposed
termi-

nals
.
Use
extreme
caution
when
working
onacar
with
the
ignition
switched
on
or
the
engine
run-
ning
.

"
Do
not
touch
or
disconnect
any
high
voltage
ca-

bles
from
the
coils
or
spark
plugs
while
the
engine

is
running
or
beingcranked
by
the
starter
.

"
Connect
and
disconnect
the
DME
system
wiring
and
test
equipment
leads
only
when
the
ignition
is
switched
off
.

"
Gasoline
is
highly
flammable
and
fts
vaporsare

explosive
.
Do
not
smoke
or
work
on
a
car
near
heaters
or
other
fire
hazards
when
diagnosing
and
repalring
fuel
system
problems
.
Have
a
tire
extinguisher
avaílable
in
case
of
an
emergency
.

"
When
working
onan
open
fuel
system,
wear
suit-
able
hand
protection,
asprolonged
contact
wfth
fuel
can
cause
illnesses
and
skin
disorders
.

"
Renew
fuel
system
hoses,
clamps
and
O-rings
any
timethey
are
removed
.

"
Before
makingany
electrical
tests
that
require
the
engine
to
be
cranked
using
the
starter,
disable
the
ignition
system
as
described
in
120
Ignition
System
.

CAUTION-

"
Prior
to
disconnecting
the
battery,
read
the
bat-
tery
disconnectinn
cautions
given
at
the
front
of
this
manual
onpage
vifi
.

"
Do
not
connect
any
test
equipment
that
delivers

a
12-volt
power
supply
to
terminal
15
(+)
of
the
ig-

nitioncoil
.
The
current
flow
may
damage
the

ECM
.
In
general,
connect
test
equipment
only
as

speclfied
by
BMW,
this
manual,
or
the
equipment

maker
.

"
Only
use
a
digital
multlmeter
for
electrical
test
.

"
Only
use
an
LED
test
light
for
quick
tests
.

"
Disconnecting
the
battery
may
erase
fault

code(s)
stored
in
memory
.
Check
for
fault
codes

prior
to
disconnecting
the
battery
cables
.
ff
the

Check
Engine
light
ís
illuminated,
see100En-
gine-General
for
DME
fault
code
information
.
ff
any
other
system
faults
have
been
detected
(indi-
catedbyan
illuminated
warning
light),
see
an
au-
thorized
BMW
dealer
.
Additional
systems
with
self-diagnostic
capabilities
include,
ABS
(Anti-
lock
brakes),
SRS
(Airbags),
EML
and
ASC+T
and
AST
(Traction
Control)
.

"
Do
not
run
the
engine
wfth
any
of
the
spark
plug
wires
dlsconnected
.
Catalytic
converter
damage
may
result
.

"
Always
waitat
least
40
seconds
afterturning
off
the
ignition
before
removing
the
engine
control
module
(ECM)
connector
.
ff
the
connector
isre-
moved
before
this
time,
residual
power
in
the
sys-
tem
relay
may
damage
the
control
module
.

"
Cleanliness
is
essential
when
working
onan
open
fuel
system
.
Thoroughly
clean
fuel
line
con-
nections
and
surroundlng
areas
before
loosen-
ing
.
Avoid
moving
the
car
.
Only
fnstall
cleanparts
.

"
Fuel
system
cleaners
and
other
chemical
addi-
tives
other
than
those
specifically
recommended
by
BMW
may
damage
the
catalytic
converter,
the
oxygensensor
or
other
fuel
supply
components
.

130-24



FUEL
INJECTION

Jo
'0

o_A

í1
RELAY

..
.
.

CAMSHAFT
POSITION
SENSOR

'
.
~'



~
:UhI~IIUH~W~`bY~7~d~t~II7

.
.
.
,

1111111
~ilf

ASC

TERMINAL
15

MEMORY
POWER

CRANKSHAFT
POSITION
qtcMSENSOR

THROTTLE
POSITION

ENGINE
COOLANT
TEMP

FUELTANK
PRESSURE
SENSOR

S-EML
S-MSR

S-ASC

VEHICLE
SPEED

LOW
FUEL
LEVEL

A/C
SWITCH
ON
(AC)
E36
IHKA



COMPRESSOR
"ON"
SIGNAL
(KO)

INDIVIDUAL
SERIAL
NUMBER

SIEMENS
MS
41
.
1
COMPONENT
REPLACEMENT

FUEL
PUMP
RELAY
CONTROL
AUX
GROUND
P

MAIN
GROUND
AC
COMPRESSOR
RELAY
CONTROL



~®

SECONDARY
AIR
INJECTION
AIR
PUMP
RELAY
CONTROL
-
M

PRE
CAT



POST
CAT
m
nXYGEN
SENSOR

ys
U
~
4



,
HEATING

FUELINJECTOR
CONTROL
(

MS
41
.1



(

MS

PURGE
CONTROL
VALVE



//



PURGE
'
CANISTERSHUT-OFF
VALVE

ECM
RELAY
CONTROL

IGNITION
COILS
CONTROL

1
ASC

o
ayi

THROTTLE
POTENTIOMETER
POWER

,

al
;
..
i

r71a
.

"a
fn7111,
/



r

Fig
.
36
.
Siemens
MS
41
.1
OBD
II
engine
management
system
usedon
M52
engine
.
Bosch
M5
.2
systemusedon
M44
engine
is
similar
.

Component



Model
Year



Location



Refer
to

Heater
Recirculation
Flap
Actuator



1992-1998



Below
left
dash
right
side
of
steering
column

HeaterBlowerMotor
Resistor
Pack



1992-1998



Behind
center
of
dashboard

Heater
Regulator
FlapActuator



1997-1998



Right
side
of
heater
box

HeaterValve
Assembly



1992-1998



Left
rear
engine
compartment

HeatingNentilation
Relay
Box



1992-1993



Below
left
side
of
dash

HeatingNentilation
Relay



1994-1998



Left
front
footwell

High
Speed
Cooling
Fan
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

Homs,
Right/Left



1993-1998



Front
of
engine
compartment

Horn
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

Horn
Relay
(Alpine)



1994-1998



Behind
glove
compartment



Fig
.
8
.
Board
Computer/Anti-Theft



Fig
.
9
.

Idle
Speed
Control
Valve



1992-1995



Top
rearof
enginebehind
intake
manifold
(M42
engine)



Fig
.
11
.

Idle
Speed
Control
Valve



1992-1995



Top
left
side
of
engine
(M50
engine)

Idle
Speed
Control
Valve



1993-1996



Below
intake
manifold
(M50/S50US
engine)

Idle
Speed
Control
Valve



1996-1998



On
throttle
housing
(M44
engine)



Fig
.
15
.

Idle
Speed
Control
Valve



1997-1998



Left
front
of
engine
below
intake
manifold
(M52/S52US
engine)

Ignition
Coils



1992-1998



Right
of
engineunder
plastic
cover
(four-cylinder)



Fig
.
7
.

Ignition
Cofs



1992-1998



Top
of
engine
undercover
(six-cylinder)



Fig
.
17
.

Ignition
Switch



1992-1998



Right
sídeofsteering
column

Intake
Air
Resonance
Changeover



1992-1998



Leftrear
of
engine
compartment
Valve(DISA)

Intake
Air
Temperature
Sensor



1992-1995



In
mass
air
flow
sensor
(M42
engine)

Intake
Air
TemperatureSensor



1996-1998



In
top
ofair
filter
housing
(M44
engine)



Fig
.
12
.

Intake
Air
Temperature
Sensor



1992-1998



I
Left
sídeof
engine
in
intake
manifold
(six-cylinder)



-



-



I



Fig
.
13
.
Fig
.
14
.

Kick-Down
Switch
(A/T)



1
1992-1998



1
Left
footwell

Mixing
Actuators



1
1992-1998



1
Heater
box

ELECTRICAL
COMPONENT
LOCATIONS



610-15

Table
a
.
E36
Component
Locations

Knock
Sensors



1
1992-1998



1
Left
side
of
engine
block

Left
Front
Power
Window
Motor



11992-1998



/
Left
front
door

Left
Front
Window
Monitoring
Switch
1
1997-1998



1
Left
front
door
trim
panel

Left
Front
Window
Retraction
Switch
1
1992
-
1993



1
Left
front
door
handle
lock
assembly

Left
Splice
Panel



1
1992-1998



1
Under
left
side
of
dash
at
kick-panel



1



Fig
.
5
.

Main
Fuse
and
Relay
Box
(Power



1992-1998



I
Left
sideof
engine
compartment



Fig
.
2
.
Distribution
Box)
1



I

Mass
Air
Flow
Sensor



1992-1998



I
Left
side
of
engine,
intake
air
duct



Fig
.
7
.1



I
Fig
.
15
.

Continued

COMPONENT
LOCATIONS

1
.
Disconnect
negative
(-)
cable
from
battery
and
cover

negative
terminal
with
insulating
material
.

CA
UTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.

2
.
Remove
driver
sideairbag
from
steering
wheel
.
See

Driver
side
airbag,
removing
and
installing
in
this

repair
group
.

3
.
With
wheels
facing
straight
ahead
and
steering
wheel

centered,
remove
steering
wheel
.
See320
Steering
and
Wheel
Alignment
.

4
.
Remove
contact
ring
cover
(flat
plastic
ring
containing

warning
text)
from
steering
wheel,
íf
applicable
.

5
.
Disconnect
ground
wire,
if
applicable

6
.
Lift
out
plastic
lock
from
steering
wheel,
if
applicable
.

See
Fig
.
2
.

0011903

Fig
.
2
.



Airbag
contact
ring
lock(arrow)
.
Pry
out
lock
and
remove
spríng
from
behind
lock
.
Some
airbag
steering
wheels
are
not
equipped
with
contact
ring
lock
.

WARNING
-

"
The
contact
ring
lock
holds
the
contact
ring
in
the
centered
position
.
Once
the
lock
is
removed,
the
contact
ring
is
free
to
rotate
.
Do
not
allow
the
con-

tact
ring
to
rotate
once
the
lock
is
removed
.

"
If
the
contact
ring
is
accidentally
rotated
outof
center,
turn
the
ring
either
fully
clockwise
orcoun-
terclockwise,
then
turn
in
the
opposite
direction
3
complete
revolutions
until
the
alignment
arrow
canbe
seen
through
the
lock
opening
.

AIRBAG
SYSTEM
(SRS)



721-
3

Airbagcontact
ring,
replacing



7
.
Remove
mounting
nutsor
screws
from
contact
ring
.

See
Fig
.
3
.
Disconnect
wire
lead(s)
andremove
contact

The
airbag
contact
ring
is
mounted
to
the
rear
of
the
steer-



ring
from
rear
of
steering
wheel
.

ing
wheel
and
is
made
up
of
a
wireribbon
that
cofs
and
un-

coils
as
the
steering
wheel
is
tumed
.
The
contact
ring
assures
continuous
electrical
contact
to
the
driver
side
airbag
unit
.

Fig
.
3
.



Airbag
contact
ring
mounting
fasteners(arrows)
.

8
.
Installation
is
reverse
ofremoval,noting
the
following
:

"
Coat
horn
slip
ring
(electrical
contact
ring)
with
CRC
®
copper
paste
before
installing
steering
wheel
.

"
Press
on
lower
lock
until
it
ís
fully
engaged
.

"
When
installing
contact
ringlock,
make
sure
lock

spring
engages
pins
on
lock
and
lock
cover
.

"
Special
instructions
apply
when
installing
airbag

equipped
steering
wheel
.
See320
Steering
and

Wheel
Alignment
.

Early
cars
(through
1993)
:

"
Route
wiring
lead
for
horn
through
squareopening
in

steering
wheel
.

"
When
installing
a
new
contact
ring
from
BMW,
remove

locking
screw
after
installing
the
contact
ringto
steer-

ing
wheel
.
See
Fig
.
4
.

"
Lock
contact
ring
mounting
fasteners
in
place
using

lacquer
paint
or
varnish
.

0011904

Fig
.
4
.



Airbag
contact
ring
locking
screw
(arrow),
as
installed
on
new

replacement
part
from
BMW
(early
production
cars)
.

AIRBAG
SENSORS
AND
ELECTRONICS