
camshaft
secondary
drive,
causing
thecamshaft
to
"advance"
12
.5°
.
The
helical
gears
are
cut
so
that
forward
motion
of
the
gear
cup
is
transiated
into
rotational
motion
of
the
camshaft
.
See
117
Camshaft
Timing
Chain
for
testing
and
repair
infor-
mation
on
the
VANOS
system
.
DISA
(Dual
Resonance
Intake
System)
DISA,usedon
4-cylinder
engines,
is
a
dual
intake
runner
system
that
effectively
provides
the
advantages
of
both
short
and
long
intake
runners
within
the
same
engine
.
For
best
per-
formance,
long
intake
runners
aremost
beneficial
atlow-
and
mid-engine
speeds
(below
4,200
rpm),
and
short
intake
run-
ners
enhance
torque
at
high
engine
speeds
(above4,200
rpm)
.
NOTE-
The
term
DISA
comes
from
the
German
words
Differ-
enzierte
Sauganlage,
and
can
roughty
be
transiated
as
a
differing
intake
manifold
configuration
.
The
DISA
solenoid
valve
is
controlled
by
the
DME
control
module,
using
engine
speed
as
the
primary
input
.
The
main
components
of
the
system
are
the
modified
twin-section
in-
takemanifoldwith
change-over
valve,
the
twin-barrel
throttle
body,
and
the
electrical/pneumatic
actuating
components
.
See
Fig
.
4
.
r
I
I
I
?
,
in
UpPer,
take
-1
manifold
1
-1
Throttle
housing
(Heated)
q
:lZU
Fig
.
4
.
DISA
system
components
.
DISA
changes
the
intake
runner
length
based
on
engine
speed
.
The
DISA
system
electro-pneumatically
changes
the
intake
runner
length
through
the
twin-section
intake
manifold
and
a
change-over
butterfly
valve
.
The
change-over
valve
is
located
at
a
point
in
the
intake
manifold
where
four
pipes
come
into
two
.
When
the
change-over
valve
is
closed,
the
4-way
primary
intake
manifold
and
the
2-way
ram
air
manifold
areconnected
to
make
the
"long"
configuration
.
When
the
change-overvalve
opens,
intake
air
flow
is
redirected
through
only
the
short
4-
way
primary
intake
manifold
.
The
change-over
valve
is
held
in
the
normally
open
position
bya
spring
.
Thisallows
for
an
open
valve
in
the
event
of
sys-
tem
failure
.
During
low
andmid
enginespeeds,
the
DME
con-
trol
module
supplies
power
to
the
solenoid
valve,
which
in
turn
allows
vacuum
to
be
applied
lo
the
vacuum
diaphragm
.
This
causes
the
valve
to
close
(long-pipe
configuration)
.
When
en-
gine
speed
reaches
approximately
4,800
rpm,
the
DME
con-
trol
module
electrically
signals
the
solenoid
valve
and
the
valve
opens,
creating
the
short
pipe
configuration
:
Further
detafs
on
DISA
canbefound
in
130
Fuel
Injection
.
Engine
Management
System
Al¡
enginescoveredby
this
manual
usean
advanced
engine
management
system
called
Digital
Motor
Electronics
(DME)
.
In
the
DME
system,
advancedOn-Board
Diagnostics
(OBD),
fuel
injection,
ignition,
and
otherfunctions,
are
combined
under
the
control
of
theEngine
Control
Module
(ECM)
.
See
Fig
.
5
.
-
Lower
intake
manifold
DISAvacuum
'
~servo
EíY1z
ENGINE-GENERAL
100-
3
le
-
DISA
solenoid
valve
0012591
/
with
butterfly
va¡
GENERAL

100-4
ENGINE-GENERAL
'
TEMP
PRECAT
POST
CAT
OXYGENSENSOR
HEATING
#
.
THROTTLE
POSITION
FUEL
INJECTOR
CONTROL
(SEQUENTIAL)
OPERATING
POWER
00
CAMSHAFT
POSITION
SENSOR
ECM
I
MAIN
GROUND
RELAY
J_
-
AC
COMPRESSOR
RELAY
CONTROL
TERMINAL
15
MEMORY
POWER
FUEL
PUMP
RELAY
CONTROL
AUX
GROUND
P
CRANKSHAFT
POSITION
dESENSOR
INTAKE
AIR
ENGINE
COOLANT
TEMP
FUEL
TANK
PRESSURE
SENSOR
S-EML
S-MSR
ASC
S-ASC
VEHICLE
SPEED
LOW
FUEL
LEVEL
A/C
SWITCH
ON
(AC)
E36
IHKA
COMPRESSOR"ON"
SIGNAL
(KO)
INDIVIDUAL
SERIAL
NUMBER
MS41
.1
SECONDARY
AIR
1NJECTION
AIR
PUMP®
RELAY
CONTROL
IDLE
CONTROL
VALVE
'M
FUEL
INJECTION
(TI)
ENGINE
SPEED
(TD)
Fig
.
5
.
Siemens
MS
41
.1
OBD
II
engine
management
systemusedon
1996
and
later
M52
engines
.
GENERAL
IGNITION
COILS
CONTROL
L
r"Q
if~
CIYVFIYC
CHE
AMP
CONTROL
ENGINE
THROTTLE
POSITION
6
ECM
RELAY
CONTROL
ASC
THROTTLE
..
:
.
.
..
-11
1Q\\\
POTENTIOMETER
POWER
CAN
TCM
II
SCAN
(DES
;
ER
DIAGNOSIS
OBD
II
I
II
GENERIC
SCANTOOL
0012596

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

100-
1
4
ENGINE-GENERAL
0013131
Fig
.
13
.
Main
chassis
ground
(arrow)
inleft
front
of
engine
compart-
ment
.
Fuel
Supply
For
the
engine
tostart
and
run
properly,
the
injection
sys-
tem
must
deliver
fuel
in
precise
proportion
to
the
amount
of
air
entering
the
engine
.
Todo
this,
the
injection
system
requires
an
unrestricted
supply
of
fuel
from
the
fuel
pump
.
If
the
fuel
pump
is
not
working,
the
engine
will
notrun
.
If
the
fuel
filter
or
a
fuel
line
is
restricted,
the
engine
may
run
poorly
.
If
the
restriction
is
severe
enough
the
engine
will
not
start
.
lf
fuel
delivery
problemsare
suspected,
perform
the
tests
de-
scribed
in
160
Fuel
Tank
and
Fuel
Pump
.
The
fuel
pressure
created
by
the
fuel
pump
is
controlled
by
a
pressure
regulator
thatreturns
excess
fuelto
the
tank
.
Any
change
in
fuel
pressure
will
cause
a
change
in
the
base
air-fuel
mixture
delivered
to
the
engine
.
If
the
fuel
pressure
is
too
low,
the
base
air-fuel
mixture
will
be
lean
.
lf
the
fuel
pressure
is
too
high,
the
base
mixture
will
be
rich
.
Fuel
pressure
tests
aredescribed
in
160
Fuel
Tank
and
Fuel
Pump
and130
Fuel
Injection
.
NOTE-
Fuel
pressure
tests
require
a
pressure
gauge
.
If
thistoolís
not
avaílable,
the
tests
can
be
performed
byan
authorized
BMW
dealer
or
other
qualified
shop
.
DRIVEABILITY
TROUBLESHOOTING
Properly
operating
fuel
injectors
play
amajor
role
in
fuel
de-
livery
.
The
DMEECM
switches
the
injectors
on
and
off
at
the
negative
(-)
or
ground
side
of
the
connectors
.
Posítíve
(+)
bat-
tery
voltage
is
always
present
at
the
connectors
when
theen-
gine
is
running
.
An
injector
that
fails
or
loses
power
will
not
open,
creating
a
lean
air-fuel
mixture
and
causing
the
engine
to
run
poorly
when
coldor
stumble
on
acceleration
.
An
injector
that
shorts
to
ground
will
remain
open
constantly
when
the
en-
gine
is
running,
creating
a
richair-fuel
mixture
that
can
dilute
engine
oil,
foul
the
spark
plugs,
cause
a
rough
idle,
and
damage
the
catalytic
converter
.
Table
e
lists
additional
symptoms
of
common
engine
drive-
ability
problems,
their
probable
causes,
and
the
suggested
corrective
actions
.
The
entries
in
boldtype
in
the
corrective
action
column
indicate
the
repair
groups
where
applicable
test
and
repair
procedures
can
befound
.
NOTE-
Most
of
the
symptoms
fisted
in
Table
e
will
also
cause
the
Check
Engine
light
to
come
on
.
If
the
light
is
on,
check
for
any
stored
faults
as
the
first
step
ín
trouble-
shooting
driveability
complaints
.

110
Engine
Removal
and
Installation
GENERAL
.
.
.
.
.......
.
.
.
..........
.
...
110-1
Engine,
removing
and
installing
(4-cylinder
engines)
.
..
.....
..
...........
110-1
ENGINE
REMOVAL
AND
INSTALLATION
110-1
Engine,
removing
and
installing
(6-cylinder
engines)
..
...
...
..
.....
..
....
110-4
GENERAL
Some
special
tools
are
required
for
removal
and
installation
of
the
engine
.
Be
sure
to
have
the
necessary
equipment
on
hand
before
starting
thejob
.
CAUTION-
"
Engine
removal
requires
disconnecting
the
bat-
tery
.
This
may
erase
any
system
fault
code(s)
that
havebeen
stored
in
control
unit
memories
.
Check
forfault
codes
prior
to
disconnecting
the
battery
cables
.
"
If
the
Check
Engine
lightis
illuminated
with
the
engine
running,
see
100
Engine-General
for
On-Board
Diagnostics
(08D)
fault
code
infor-
mation
.
"
If
any
other
system
faults
have
been
detected,
as
indicated
by
an
illuminated
ANTI
LOCK,
SRS
or
AST
warning
light,
see
the
appropriate
repair
group
inthis
manual
or
an
authorized
BMW
dealer
for
more
information
on
fault
codes
.
ENGINE
REMOVALAND
INSTALLATION
Engine,
removing
and
installing
(4-cylinder
engines)
Cover
al¡
painted
surfaces
before
beginning
theremoval
procedure
.
Asan
aid
to
installation,
label
al¡
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
.
1.
Disconnect
negative
(-)
cable
from
battery
in
luggage
compartment
.
0011969
CAUTION-
Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.
ENGINE
REMOVAL
AND
INSTALLATION
110-1
2
.
Remove
transmission
from
car
.
See230
Manual
Transmission
or
240
Automatic
Transmission
.
3
.
Remove
enginehood
or
place
hood
in
service
positíon
.
See
410
Fenders,
Engine
Hood
.
NOTE-
tt
is
notnecessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.
4
.
Remove
splash
guard
under
engine,
if
applicable
.
5
.
Unbolt
ignition
coil
assembly
from
bracket
on
strut
tow-er
.
Disconnect
wiring
to
ignition
cofs,
then
place
coil
assembly
on
engine
.
6
.
Disconnect
al¡
cables
and
harness
connectors
at
throt-
tle
housing
.
7
.
Unbolt
andremove
complete
air
cleaner
housing
with
mass
air
flow
sensor,
disconnecting
and
labeling
con-
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
1
.
Fig
.
1
.
Intake
air
duct
hose
clamp
(A),
mass
air
flow
sensor
connec-
tor
(B),
and
air
cleanerto
air
flow
sensor
clips
(C)
on
M44
en-
gine
.
ENGINE
REMOVAL
AND
INSTALLATION

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

110-
4
ENGINE
REMOVAL
AND
INSTALLATION
Engine,
removing
and
installing
(6-cylinder
engines)
Engineremoval
procedures
for
the
various
6-cylinder
en-
gines
arecovered
in
this
section
.
Most
steps
in
theproce-
dures
are
similar
or
the
same
for
al¡
engines
.
Specific
differences
that
apply
are
noted
at
the
beginning
of
each
step
.
Be
sure
to
cover
all
painted
surfaces
before
beginning
the
removal
procedure
.
As
an
aid
to
installation,
label
all
compo-
nents,wires,
and
hoses
before
removing
them
.
Do
not
reuse
gaskets,
O-rings
or
seals
during
reassembly
.
WARNING
-
Due
to
risk
of
personal
injury,
be
sure
the
engine
is
cold
before
beginning
the
removalprocedure
.
1
.
Disconnect
negative
(-)
battery
cable
in
luggage
com-
partment
.
CAUTION-
Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
vi¡¡
.
2
.
Remove
engine
hood
or
place
hood
in
service
position
.
See410
Fenders,
Engine
Hood
.
NOTE-
1t
is
not
necessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.
3
.
Remove
splash
guardunder
engine,
if
applicable
.
4
.
Remove
transmission
from
car
.
See
230
Manual
Transmission
or
240Automatic
Transmission
.
5
.
Remove
vacuum
hosefrom
brake
booster
on
bulkhead
.
Cover
hole
in
booster
and
plug
hose
end
.
6
.
Remove
intake
air
plenum
panel
in
rear
of
engine
com-
partment
.
See
640
Heating
and
AirConditioning
.
7
.
Remove
ground
strap
from
timing
case
cover,
if
appli-
cable
.
8
.
Remove
top
enginecovers
and
disconnect
ignition
coil
harness
connectors
.
Working
at
fuel
injectors,
pry
open
small
wire
clipsat
each
injector
.
Remove
main
harness
hold-down
nuts
and
lift
completeharness
away
.
See
Fig
.
7
.
ENGINE
REMOVAL
AND
INSTALLATION
Fig
.
7
.
Remove
mainharnessfrom
top
engine
and
place
at
base
of
windshield
.
0012703
Fig
.
8
.
Mass
air
flow
sensor
connector
air
duct
hose
clamp,
and
air
cleaner
housing
mounting
bolts
(arrows)
.
9
.
Unbolt
andremove
complete
air
cleaner
housing
with
10
.
On
cars
with
automatic
transmission,
remove
front
and
mass
air
flow
sensor,
disconnecting
and
labeling
con-
rearbrackets
holding
transmission
cooler
linesto
side
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
8
.
of
engine
.