020-6
MAINTENANCE
PROGRAM
Group
310/330
Table
c
.
Inspection
II
Service
a
d
d
a
a>
0
d
a
r
.c
mm
L
m
y
L
E
ó
3
E
ó
Maintenance
ítem
l
o-
z
~
c
Engine
compartment
maintenance
Inspect
V-belt
/Poly-ribbeddrive
condition
.
Check
V-belt
tension,
if
applicable
.
Lubricate
throttle
linkage
.
Replace
air
filter
.
Change
oil
and
oil
filter
.
Replacespark
plugs
.
Repair
Group
120
Check
brake/clutch
fluid
leve¡
.
Check
battery
acid
leve¡
and
correct
asnecessary
.
Repair
Group
121
Check
engine
coolant
leve¡
and
anti-freeze
protection
and
add
asnecessary
.
Inspect
for
cooling
system
leaks
.
Repair
Group
170
Under
car
maintenance
Change
automatic
transmission
fluid
.
Repair
Group
240
Change
manual
transmission
oil
.
Repair
Group
230
Check
clutch
plate
for
wear
.
Repair
Group
210
Check
drive
axle
boots
for
leaks
.
Repair
Group
330
Change
final
drive
fluid
(1995
and
later
models
:
change
synthetic
oil
every
2nd
Inspection
II)
.
Replace
fuel
filter
.
Check
fuel
tank,
fuel
lines,
and
af
connections
for
leaks
.
Inspect
exhaust
system
.
Repair
Group
180
Check
steering
gear
and
steering
¡inkages
.
Check
power
steering
system
for
leaks
.
Check
fluidleve¡
.
Repair
Group
320
Inspect
brake
system
for
damaged
hoses
and
lines,
leaks
or
damage
.
Remove
calipers
and
check
brake
pad
wear
.
Check
brake
rotors
for
scoring
damage
.
Repair
Group
340
Check
parking
brake
operation,
adjust
cable
if
necessary
.
Check
thickness
of
parking
brake
lin-
ings
.
Repair
Group
340
Inspect
front
and
rear
suspension,
including
front
and
rear
wheel
bearings,
for
play
.
Repair
Inspect
wheels
and
tires,
including
spare,
check
tire
pressure
and
condition
.
Body
and
Interior
Maintenance
Lubricate
door
hinges
and
hood
latch,
hood
hinges
.
Check
headlight
and
driving
light
aiming
and
adjust
asnecessary
.
Check
operation
of
headlights,
parking
lights,
back-up
lights,
licenseplate
lights,
interior
lights,
glove
box
light,
engine
compartment
light,
trunk
light,
instrument
panel
lights,
turn
signals,
emer-gency
flashers,
stop
lights,
horns,
headlight
flasher
anddimmer
switch
.
Check
active
check
control
panel
forfauits
(where
applicable)
.
6
Electrical
System
MAINTENANCE
TABLES
Continued
on
next
page
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
.
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
11
.
Detach
wiring
harness
duct
at
rear
bulkhead
panel
and
pull
complete
duct
forward
and
up
to
allow
access
to
rear
of
cylinder
head
cover
.
12
.
Remove
spark
plugs
and
spark
plugwire
loom
.
"
Remove
plastic
cover
from
top
of
cylinder
head
.
"
Disconnect
spark
plug
wires
fromspark
plugs
and
re-
move
spark
plugs
.
"
Unbolt
spark
plug
cable
harness
and
heat
shield
from
right
side
of
cylinder
head
cover
and
set
aside
.
13
.
Unscrew
andremove
cylinder
head
cover
cap
screws
and
remove
cover
.
See
Fig
.
5
.
CAUTION-
Two
of
the
cover
hold-down
screws
are
under
the
spark
plug
cable
duct
.
NOTE-
Make
note
of
the
arrangement
of
cap
screws,
washers
and
rubber
grommets
holding
the
cylinder
head
cover
in
place
.
Fig
.
5
.
Cylinder
head
cover
mounting
points
(arrows)
.
Fig
.
7
.
M44
fuel
rail
air
connection
(A)
and
fuel
supply
and
return
lines
Intake
manifold,
removing
(B)
.
14
.
On
late
engines,
disconnect
injector
air
shrouding
hose
from
fitting
at
center
of
upper
intake
manifold
.
18
.
Disconnect
fuel
supply
and
return
lines
from
fuel
rail
.
15
.
Remove
upper
section
of
intake
manifold
.
"
Disconnect
ali
cables
harness
connectors
from
throttle
housing
and
intake
manifold
.
"
Disconnect
fuel
tank
vent
hose
fromvent
valve
on
low-
er
sitie
of
manifold
.
"
Remove
manifold
support
brackets
.
See
Fig
.
6
.
"
Remove
upper-to-lower
manifold
fasteners
(1
bolt,
2
nuts)
and
separate
upper
manifold
from
lowermani-
fold
.
Note
locating
dowei
sleeves
on
lower
to
upper
manifold
mounting
studs
.
Remove
dowels
and
set
aside
.
See
Fig
.
8
.
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
113-3
0012686
Fig
.
6
.
Intake
manifold
support
brackets
and
mountinghardware
.
Manifold
for
M44
engine
shows
.
16
.
Disconnect
oil
dipstick
tube
bracket
from
lower
manifold
section
.
17
.
On
M44
engine,
relieve
fuel
pressure
using
com-
pressed
air
(maximum
3
bar
pressure)
at
schroeder
valve
on
fuel
rail
.
Briefly
apply
air
pressure
to
force
fuel
back
intofuel
tank
.
See
Fig
.
7
.
WARNING
-
"
The
fuel
system
retains
fuel
pressure
when
the
engine
is
off
(up
to
75
psi)
.
Use
care
when
dis-
connecting
fuel
lines
.
Unscrew
the
fuel
tank
cap
to
retease
pressure
in
the
tank
.
Wrap
a
clean
shop
towel
around
the
fitting
when
loosening
.
"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
worknear
heaters
or
other
tire
hazards
.
Placea
tire
extin-
guisher
in
the
vicinity
of
the
work
area
.
19
.
Disconnect
coolant
hoses
from
vent
valve
on
lower
intake
manifold
.
Remove
crankcase
vent
valve
from
manifold
.
CYLINDER
HEAD,
4-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
.
Fig
.
27
.
Remove
top
enginecovers
by
prying
out
plugs
and
removing
nuts
(A)
.
Make
sure
rubber
insulators
on
either
side
of
large
cover
do
not
fall
off
during
cover
removal
(B)
.
Fig
.
28
.
Fuel
injection
harness
beíng
lifted
off
engine
to
be
placed
at
base
of
windshield
(A)
.
Ignitioncoils
are
also
visible
(B)
.
M50
engine
shown,
other
6-cylinder
engines
are
similar
.
14
.
Remove
cylinder
head
cover
mounting
bolts
and
re-
move
cylinder
head
cover
.
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
113-
11
15
.
Remove
oil
baffle
cover
from
above
intake
camshaft
.
See
Fig
.
29
.
Fig
.
29
.
Camshaft
oil
baffle
coverbeing
removed
.
NOTE-
The
cylinder
head
cover
mounting
bolt
insulators
and
13
.
Remove
hold
down
nuts/bolts
from
fuel
injection
har-
gaskets
should
be
reinstalled
in
the
same
order
.
Make
ness
.
Pry
back
injector
connector
retaining
clips
and
lift
note
of
their
arrangement
during
removal
.
entire
harness
off
engine
.
See
Fig
.
28
.
Intake
manifold,
removing
811119
16
.
Disconnect
vacuum
hose
from
brake
system
vacuum
booster
.
Plug
opening
in
booster
.
17
.
Remove
throttle
housing
mounting
bolts
and
remove
throttle
housing
.
Set
throttle
housing
aside
without
dis-
connecting
cablesor
coolant
hoses
.
See
Fig
.
30
.
Fig
.
30
.
Remove
4
comer
bolts
(arrows)
from
throttle
housing
and
unbolt
complete
assembly
from
intake
manifold
.
Remove
complete
throttle
assembly
without
disconnecting
connec-
tors,
hoses
or
cables
.
(M50
engine
shown
.)
CYLINDER
HEAD,
6-CYLINDER
130-20
FUEL
INJECTION
Fig
.
29
.
Throttleposition
sensor
terminal
identification
on
M50
engine
.
Tableg
.
Throttle
Position
Sensor
Tests
(DME3
.113
.3
.1)
Test
conditions
I
Terminals
I
Testvalue
Harness
connector
13
andground
15
VDC
(approx
.)
disconnected,
igni-
in
harness
tion
on
connector
Harness
connector
1
and3
at
sen-
14
k
ohms
(approx
.)
disconnected,
igni-
sor
terminals
tion
off
Throttle
plate
rotat-
1
and
2
at
sen-
Variable
from
1
-
4ked
from
¡dieto
full
sor
terminals
ohms
(approx
.)
with-
throttle
position
out
interruption
¡die
Speed
Control
Valve
Coil
Resistance
Values
"
M50/S50US
engine
NOTE-
Terminals
1
and
2
..
.
................
20
t
5
ohms
On
cars
with
tractioncontrol,
do
not
confuse
the
throttle
Terminals
2
and
3
...................
20
t5
ohms
position
sensor
on
the
main
throttle
body
with
the
throt-
Terminals
1
and
3
..
.
..
:
............
.40
t
5
ohms
tle
positionswitch
on
the
secondary
throttle
body,
where
applicable
.
¡die
speed
control
valve,
testing
¡die
speed
is
maintained
by
the
ECM
through
the
¡die
speed
control
valve
.
The
¡die
controlfunction
compensates
for
engine
load
and
engine
operating
conditions
.
¡die
speed
is
adaptive
through
the
ECM
and
no
¡die
speed
adjustments
can
be
made
.
NOTE-
Before
testing
the
valve,
confirm
that
the
throttle
position
The
idle
speed
controlvalve
receives
positive
(+)
bat-
sensor
is
working
correctly
.
tery
voltage
from
the
main
relay
.
BOSCH
DME
M3
.
1
AND
M3
.3
.1
COMPONENT
TESTS
AND
REPAIRS
NOTE-
"
The
tests
given
below
are
electrical
checks
only
.
They
do
not
check
the
mechanical
operation
of
the
valve
.
If
the
valve
is
suspected
of
causing
poor
idie,
substitut-
ing
a
known
good
valve
is
the
best
way
to
check
for
a
mechanical
fault
.
1
.
With
engine
running,
check
that
¡die
speed
control
valve
is
buzzing
.
2
.
Turn
on
A/C
or
shift
car
finto
drive
.
¡die
should
remain
steady
orincrease
slightly
.
3
.
If
valve
is
not
buzzing,or
if
¡die
decreases
in
step
2,
stop
engine
and
disconnect
harness
connector
from
valve
.
Check
resistance
of
valve
across
its
terminals
.
See
Fig
.
30
.
Test
values
are
listed
below
.
NOTE
-
If
you
suspect
an
intermittent
fault,
lightly
tapthe
valve
while
testing
resistance
.
11250
Fig
.
30
.
¡die
speed
control
valve
terminal
identification
.
4
.
With
valve
harnessconnector
disconnected,
check
for
battery
voltage
at
red/white
wire
in
connector
with
igni-
tion
tumed
on
.
"
If
there
is
no
voltage,
check
wiring
between
connec-
tor
and
main
relayterminal
87
.
See
Electrical
Wiring
Diagrams
.
5
.
If
voltage
is
presentas
described
above,
check
wiring
between
ECM
and
valve
.
If
no
wiring
faults
are
found,
check
ECM
signal
to
valve
.
NOTE-
NOTE-
"
The
Ole
speed
control
valve
signal
can
be
checked
The
intake
manifold
is
held
in
place
with
7
nuts
from
using
a
duty
cycle
meter
(or
dwellmeter)
.
Connect
the
above
and
2
support
bracket
bolts
from
undemeath
.
On
meter
to
the
valve
following
the
manufacturer's
in-
DME
3
.1
cars,
carefully
disconnect
the
idleair
hose
from
structions
.
Turn
on
the
WC
or
create
a
larga
air
leak
theintake
manifold
when
lifting
the
manifold
off
.
For
more
and
check
that
the
meter
reading
reacts
while
the
idle
information,
sea
113
Cylinder
HeadRemovaland
In-
speed
remainssteady
.
stallation
.
"
There
are
some
additional
inputs
to
the
control
mod-
ule
that
affect
idle
speed
(Le
.
throttle
position,
AIC-on
5
.
Disconnect
al¡
necessary
hoses
andremove
idle
speed
signals,
andAIT
Drive
position)
.
Check
these
signals
control
valve
.
if
idle
problems
persist
.
See
Tabla
i
orTable
j
.
Idle
speed
control
valva,
replacing
The
idle
speed
control
valve
is
mounted
beneath
the
intake
manifold
.
Accessing
the
valva
is
best
accomplishedby
first
re-
moving
the
intake
manifold
.
NOTE-
¡tis
recommended
that
the
intake
manifold
gaskets
be
replaced
whenever
the
intake
manifold
is
removed
.
1
.
Remove
top
enginecovers
from
engine
.
See
Fig
.
31
.
FUEL
INJECTION
130-21
6
.
Installation
is
reverse
of
Removal
.
Use
new
gaskets
when
installing
intake
manifold
.
NOTE-
Poor
driveability
may
be
noticed
afterinstalling
a
re-
placement
idle
speed
control
valve
.
After
about
10
min-
utes
of
driving,
the
system
will
adapt
the
base
setting
of
the
valva
and
the
idle
speed
should
retum
to
normal
.
Tightening
Torque
"
Intakemanifold
to
cylinder
head
(M7)
........
..
.
15±2
Nm
(11
ti
ft-Ib)
BOSCH
DME
M5
.2
COMPONENT
REPLACEMENT
On-Board
Diagnostics
11
(OBD
II)
is
incorporated
into
the
Bosch
DME
M5
.2
engine
management
systems
used
on
the
M44
engine
.
OBD
II
is
capable
of
detecting
a
full
range
of
faults
.
When
faults
are
detected,
a
Diagnostic
Trouble
Code
(DTC)
is
stored
in
the
system
ECM
.
The
Check
Engine
warn-
ing
light
will
also
come
on
if
an
emissions-relatad
fault
is
de-
tected
.
The
most
efficient
way
to
diagnose
the
Bosch
OBD
II
sys-
tem
is
by
using
a
specialized
scan
tool
.
The
OBD
II
system
is
capable
of
storing
hundreds
of
faults,
making
diagnostics
with
a
scan
tool
the
only
viable
method
.
Therefore,
system
diag-
nostics
is
not
covered
here
.
Fi
31
.
Remove
to
en
ine
covers
b
in
out
caPs
and
removin
NOTE-
nuts
(A)
9
.
P
g
y
Pry
g
g
"
The
OBD
11
fault
memory
(including
an
iiluminated
Note
14
L-te
at
cover
edge
(arrows)
.
Check
Engine
light)
can
only
be
reset
using
the
spe-
cial
scan
tool
.
Removing
the
connector
from
the
ECM
2
.
Remove
two
hold
down
nuts
from
fuel
injector
wiring
or
disconnecting
the
battery
will
not
arase
the
fault
duct
.
Pry
back
injector
connector
retainers
and
lift
off
memory
.
wiring
duct
.
"
The
16-pin
OBD
Il
diagnostic
connector
is
located
on
the
lower
left
dash
panel
.
Refer
to
Fig
.
1
.
3
.
Disconnect
intake
air
bootfrom
throttle
housing
.
Where
applicable
disconnect
accelerator
cable
and
cruise
"
BMW
special
scan
tool
ora
`generic"OBD
II
scan
tool
control
cable
from
their
brackets
.
must
be
used
to
access
DTCs
.
4
.
Unbolt
intake
manifold
and
move
it
out
of
way
enough
to
access
idle
speed
control
valva
.
"
Tablak
lists
engine
control
module
(ECM)
pinouts
for
the
DMEM5
.2
system
BOSCH
DME
M5
.
2
COMPONENT
REPLACEMENT