160-
1
0
FUEL
TANK
AND
FUEL
PUMP
3
.
Operate
fuel
pump
as
described
earlier
under
Operat-
ing
fuel
pump
for
tests
.
Check
that
fuel
pressure
cor-
responds
to
specifications
listed
in
Table
c
.
"
If
system
pressure
is
low,
repeat
test
whilegradually
pinching
off
return
hose
.
Pressure
should
rise
rapidly
.
If
not,fuel
pump
is
most
likely
faulty
.
"
If
system
pressure
is
too
high,
check
return
line
from
pressure
regulator
to
tank
.
Check
for
kinks
in
hose
.
Blow
compressed
air
through
line
to
check
for
block-
ages
.
If
no
faulty
canbe
found,
pressure
regulator
is
most
likely
faulty
.
See
130
Fuel
Injection
for
testing
and
replacementprocedures
.
Table
c
.
Fuel
Pressure
Specifications
Engine
1
Fuel
pressure
4-cylinder
M42/M44
3
.0
:e
0
.06
bar(43
.5
±0
.9
psi)
6-cylinder
M50/S50US
3
.0
:j-
0
.06bar(43
.5
t0
.9
psi)
M52/S52US
3
.5
t
0
.06
bar
(51
t0
.9psi)
CA
UTION-
Do
not
use
compressed
air
above
40
psi
to
blow
out
fines
or
components
.
Interna¡
damage
to
com-
ponents
may
result
.
4
.
When
finished,
disconnect
pressure
gauge
.
FUEL
PUMP
Fuel
delivery
volume,
testing
1
.
Disconnect
return
line
from
fuel
rail
in
engine
compart-
ment
.
2
.
Connect
a
length
of
hose
to
fitting
on
fuel
rail
and
place
open
end
of
hose
in
a
suitable
container
for
catching
fuel
(2-quart
capacity)
.
3
.
Run
fuel
pump
for
exactly
30
seconds
as
described
earlier
under
Operating
fuel
pump
for
tests
and
mea-
sure
fuel
collected
.
Refer
to
Table
d
.
WARNING-
Table
d
.
Fuel
Pump
Delivery
Specifications
Fuel
under
pressure
is
present
duringthe
test
.
Use
I
Engine
Delivery
rate
(30
seconds
@
12V)
hose
clamps
at
all
connections
.
4-cylinder
M42/M44
0
.875
fter
(0
.93
qt)
6-cylinder
M50/S50US
0
.875
fter(0
.93
qt)
M52/S52US
~
1
.12
liter
(1
.16
qt)
4
.
When
finished
testing,
reconnect
fuel
line
.
Tighten
all
hose
clamps
.
NOTE-
It
is
common
practice
to
replace
the
fuel
filter
any
time
the
fuel
pump
unit
is
replaced
.
170-2
RADIATOR
AND
COOLING
SYSTEM
Cooling
Fans
TROUBLESHOOTING
Belt-driven
coolingfan
.
The
primary
cooling
fan
is
belt-
driven
.
It
is
mounted
to
the
frontof
the
coolant
pump
through
a
fan
clutch
.
The
fan
clutch
is
a
viscous
fluid
coupling
that
con-
trols
the
speed
of
thefan
based
on
engine
compartment
tem-
perature
.
Electric
cooling
fan
.
Models
with
M44
engine
and
stan-
dard
transmission
substitute
an
electric
fan
for
the
belt-driven
viscous
fan
.
This
is
attached
to
the
rear
of
the
radiator
and
controlledvia
the
DME
5
.2
engine
management
system
.
NOTE-
The
electric
cooling
fan
in
these
models
is
activated
by
the
engine
control
module
(ECM)
.
Auxiliary
coolingfan
.
In
al¡
models
a
two-speed
electric
auxiliary
cooling
fan
is
mounted
behind
the
front
grill
and
in
front
of
the
radiator
.
This
fan
is
primarily
used
for
the
A/C
sys-
tem,
but
also
operates
when
the
coolant
temperature
ex-
ceeds
a
predetermined
leve¡
.
Warnings
and
Cautions
The
following
warnings
and
Cautions
should
beobserved
when
working
on
the
cooling
system
.
WARNING
-
"
Atnormal
operating
temperature
the
cooling
sys-
tem
is
pressurized
.
Allow
the
system
to
cool
as
long
as
possible
before
opening-a
minimum
of
an
hour-then
release
the
cap
slowly
to
allow
sale
release
of
pressure
.
"
Releasing
the
cooling
system
pressure
lowers
the
coolants
boiling
point
and
the
coolant
may
boíl
suddenly
.
Use
heavy
gloves
and
wear
eye
and
laceprotection
to
guard
against
scalding
.
"
Use
extreme
care
when
draining
and
disposing
of
engine
coolant
.
Coolant
is
poisonous
and
lethal
to
humans
and
pets
.
Pets
are
attracted
to
coolant
because
of
its
sweet
smell
and
taste
.
Consult
a
veterinarian
immediately
if
coolant
is
ingested
byan
animal
.
CAUTION-
"
Avoidadding
cold
water
to
the
coolant
while
the
engine
is
hot
or
overheated
.
If
it
is
necessary
to
add
coolant
to
ahot
system,
do
so
only
with
the
engine
running
and
coolant
pump
tuming
.
"
Prior
to
disconnecting
the
battery,
read
the
bat-
tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.
TROUBLESHOOTING
Most
cooling
system
faults
can
be
grouped
into
one
of
three
categories
:
"
Cooling
system
leaks
"
Poor
coolant
circulation
"
Radiator
cooling
fan
faults
When
investigating
the
cause
of
overheating
or
coolant
loss,
begin
with
a
visual
inspection
.
Be
sure
to
check
the
con-
dition
and
tension
of
the
coolant
pump
drive
belt
.
Check
hoses
for
cracks
or
softness
.
Check
clamps
for
looseness
.
Check
the
coolant
leve¡
and
check
for
evidence
of
coolantleaks
from
the
engine
.
Check
that
the
radiator
fins
are
not
blocked
with
dirt
or
de-
bris
.
Clean
the
radiator
using
low-pressure
water
or
com-
pressed
air
.
Blow
outward,
fromthe
engine
side
out
.
Inspect
the
coolant
pump
by
first
removing
the
drive
belt
from
the
pump
.
Firmly
grasp
opposite
sídes
of
the
pulley
and
check
for
play
in
all
directions
.
Spin
the
pulley
and
check
that
the
shaft
runs
smoothly
.
NOTE-
The
coolant
provides
lubrication
for
the
pump
shaft,
soan
occasional
drop
of
coolant
leaking
from
the
pump
is
acceptable
.
If
coolant
drips
steadily
from
the
vent
hole,
the
pump
should
be
replaced
.
The
cooling
system
becomes
pressurized
at
normal
operat-
ing
temperature,
which
raises
the
boiling
point
of
the
coolant
.
Leaks
may
prevent
the
system
from
becoming
pressurized,
allowing
the
coolant
to
boil
at
a
lower
temperature
.
If
visual
ev-
idence
is
inconclusive,
a
cooling
system
pressure
test
can
help
to
pinpointhard-to-find
leaks
.
If
the
cooling
system
is
full
of
coolant
and
holds
pressure,
the
next
most
probable
cause
of
overheating
are
:
"
Faulty
radiator
fan
"
Loose
or
worn
drive
belt
"
Failed
thermostat
or
coolant
pump
"
Clogged/plugged
radiator
or
coolant
passages
.
NOTE
-
"
Some
early
style
coolant
pumps
were
fitted
wíth
fi-
berlplastic
type
impellers
.
Over
time,
this
impeller
can
wear
away
and
result
in
overheating
.
The
plastic
im-
peller
can
also
slip
or
free-wheel
on
the
pump
shaft
.
If
the
engine
overheats
and
no
other
faults
canbe
found,
theold
style
impeller
may
be
the
cause
of
the
problem
.
"
Only
pumps
with
the
updated
metal
impeller
should
be
used
for
replacement
.
GENERAL
.
.
.......
.
......
.
...
.
.
.
.
.
...
180-1
Exhaust
system,
removing
and
installing
.
...
.180-3
EXHAUST
SYSTEM
REPLACEMENT
.
...
180-1
Exhaust
manifolds,
removing
and
installing
.
.
.180-5
GENERAL
The
exhaust
system
is
designed
to
be
maintenance
free,
al-
though
regular
inspection
is
warranted
due
to
the
harsh
oper-
atingconditions
.
Under
normal
conditions,
the
catalytic
converter
does
not
require
replacement
unless
it
is
damaged
.
On
1996
and
later
cars,
a
pre-
and
post-catalytic
converter
oxygen
sensor
is
used
at
each
catalytic
converter
.
Be
sure
to
take
care
when
removingthe
system
not
to
damage
the
sen-
EXHAUST
SYSTEMREPLACEMENT
sors
.
See
130
Fuel
Injection
for
information
on
testing
oxygen
sensors
.
NOTE-
OnM52
engines,
two
resonator
pípes
(short
and
long)
are
incorporated
into
the
rear
muffler
assembly
.
See
Fíg
.
1
.
An
exhaust
flap
is
integrated
into
the
outlet
side
of
the
short
pipe
.
The
flap
is
operated
by
a
vacuum
ac-
tuator
via
the
Siemens
MS
41
.1
engine
control
mod-
ule)
.
The
flap
is
closed
at
engine
speeds
below
2,500
rpm
.
This
allows
exhaust
gasses
to
flow
through
the
long
resonator
pipe
and
reduce
noise
.
Above
2,500rpm,
the
exhaust
flap
is
open
(no
vacuum
applied
to
the
actuator)
and
allows
exhaust
gasses
to
flow
through
the
short
pipe
for
maximum
performance
.
180
Exhaust
System
0013101
Fig
.
1
.
Rear
muffler
(active
silencer
usedon
M52
engines)
.
Vacuum
operated
flap
(A)
changesbetween
short
and
long
pipes,
de-
pending
on
engine
speed
.
EXHAUST
SYSTEM
180-1
WARNING
-
Exhaust
gases
are
colorless,
odorless,
and
very
toxic
.
Run
the
engine
only
ín
a
well-ventilated
area
.
Immediately
repair
any
leaks
in
the
exhaust
system
or
structural
damage
to
the
car
body
that
might
al-
lowexhaust
gases
to
enter
the
passenger
compart-
ment
.
Exhaustsystem
components
are
detailed
in
Fig
.
2
through
Fig
.
4
.
New
fasteners,
clamps,rubber
mounts,
and
gaskets
should
be
used
when
replacing
exhaust
components
.
A
liberal
appli-
cationof
penetrating
oil
to
the
exhaustsystem
nuts
and
bolts
in
advance
may
make
removal
easier
.
WARNING
-
"
The
exhaust
system
and
catalytic
converter
op-
erate
at
high
temperatures
.
Allow
components
to
cool
before
servicing
.
Wear
protectíve
clothíng
to
prevent
bums
.
Do
not
use
flammable
chemicals
near
a
hot
catalytic
converter
.
"
Old,
corroded
exhaust
system
components
crumble
easíly
and
often
have
exposed
sharp
edges
.
To
avoid
injury,
wear
eye
protection
and
heavy
gloves
when
working
with
old
exhaust
parts
.
EXHAUST
SYSTEM
REPLACEMENT
T
180-
4
EXHAUST
SYSTEM
Fig
.
6
.
Exhaust
system
support
bracket
on
6-cylinder
engine
.
Re-
move
bolts
(arrows)
to
separate
from
exhaust
pipe
.
Fig
.
7
.
Rubber
exhaust
system
hangers
.
Remove
hanger
by
prying
off
bracket
(arrows)
.
EXHAUST
SYSTEM
REPLACEMENT
7
.
Installation
is
reverse
of
removal
.
"
Where
necessary,
transfer
parts
from
old
system
to
re-
placement
system
.
"
Coat
manifold
studs
with
copper
paste
before
installing
nuts
.
"
Where
applicable,
tighten
front
pípewith
semi-flexible
compensator
last
when
installing
front
pipe
to
mani-
folds
.
"
Make
sure
there
is
at
least
20
mm
(
3
/4
in
.)
of
clearance
between
exhaust
systemand
car
body
at
every
point
.
"
Loosely
install
all
exhaust
system
mountinghardware
and
hangers
before
tightening
fasteners
to
their
final
torque
.
"
On
4-cylinder
engines
:
Tighten
center
mounting
flange
nuts
evenly
until
correct
dimension
is
obtained
.
See
Fig
.
8
.
ri
J%JJ
w
~~~JJJJ
1
Fig
.
8
.
On
4-cylinder
engines,
tighten
nuts
evenly
so
that
spríngs
are
preloaded
to
Dimension
A
.
NOTE-
To
prevent
exhaust
system
rattles
and
vibration,
pre-load
the
rear
clamping
brackets
in
the
íonaard
direction
.
See
Fig
.
9
.
0011937
Tightening
Torques
"
Cross
brace
to
chassis
..
.
...
.
..
..
21
Nm
(17
ft-Ib)
"
Exhaust
support
bracket
to
transmission
.
.
.
.
.......
.....,.
21
Nm
(17
ft-Ib)
"
Exhaust
system
mounting
clamps
...
15
Nm
(11
ft-Ib)
"
Front
exhaust
pipeto
exhaust
manifold
M10
nut
.
.
.
...
.
..
..............
30
Nm
(22
ft-Ib)
"
Front
exhaust
pipe
torear
pipe
M8
bolt/nut
..
....
.
..............
22
Nm
(16
ft-Ib)
with
compression
spring
................
See
Fig
.
8
"
Oxygen
sensor
to
exhaust
pipe
.....
55
Nm
(41
ft-Ib)
8
.
Disconnect
main
harness
connector
from
transmission
by
turning
its
bayonet
lock
ring
counterclockwise
.
Re-
move
wiring
harness
from
transmission
housing
.
See
Fig
.
8
.
Fig
.
8
.
Harness
connector
at
automatic
transmission
.
9
.
Where
applicable,
disconnect
harness
connector
from
speed
sensor
at
top
óf
transmission
.
10
.
Disconnect
transmission
cooler
line
clamps
from
en-
gine
.
Disconnect
lines
from
transmission
.
11
.
Support
transmission
with
transmission
jack
.
Remove
reinforcing
cross
brace
(if
applicable)
and
transmission
support
crossmember
.
NOTE-
Note
installation
positionof
support
crossmember
.
12
.
Remove
access
plug
in
cover
plate
on
right
side
of
en-
gine
block
and
remove
torqueconverter
bolts
.
Turn
crankshaft
to
access
boits
.
See
Fig
.
9
.
AUTOMATIC
TRANSMISSION
240-
5
Bellhousing
access
hole
Socket
wrench
Fig
.
9
.
Access
andremove
torque
converter
boits
through
hole
in
bellhousing
cover
.
0
A
fij
13
.
Remove
bellhousing-to-engine
mounting
bolts
.
See
Fig
.
10
.
Transmission-to-engine
Torx-head
mounting
bolts
.
Fig
.
10
.
0012592
TRANSMISSION
REMOVAL
AND
INSTALLATION
9
.
Packeach
CV
joint
and
rubber
boot
with
specified
REAR
SUSPENSION
ARMS
amount
of
lubricant
supplied
.
Apply
adhesive
to
large
end
of
boot
and
mount
it
on
joint
.
Secure
boot
with
clamps
.
The
trailing
arms,
control
arms
and
their
mountingbushings
Apply
sealer
to
inner
CV
joint
dust
cover
and
instan
.
control
the
position
of
the
rear
wheels
.
A
damaged
suspen-
sion
arm
or
worn
bushings
will
change
the
rear
wheel
align
NOTE-
ment
and
may
adversely
affect
handling
and
stability
.
"
Before
installing
each
small
boot
clamp
be
sure
to
"burp"
the
boot
by
flexing
the
CV
joint
as
far
overas
it
WARNING
will
go
.
A
small
screw-driver
inserted
between
the
Do
notattempt
to
straighten
a
damaged
suspension
boot
and
the
axle-shaft
will
help
the
process
.
arm
.
Bending
or
heating
may
weaken
the
original
"
BMW
recommends
Bostil101513
or
EppleC4851
ad-
part
.
If
the
suspension
arm
shows
any
signs
of
hesive,
and
Epple®39
or
Curil©T
sealer
damage
or
excessive
corrosion,
it
must
be
re-
placed
.
CV
Joint
Lubricant
Capacity
"
Wheel
hub
end
ex
.
M3
..
..
.
....
.
.............
80
gram
(2.8
oz
.)
M3
..
...
.
..
.................
100
gram
(3
.5
oz
.)
"
Finaldrive
end
.................
85
gram
(3
.0
oz
.)
10
.
Install
drive
axle
as
described
earlier
.
1
.
Final
drive
carrier
2
.
Stabilizer
bar
3
.
Upper
control
arm4
.
Lower
control
arm5
.
Trailing
arm6
.
Trailing
arm
front
bracket
Fig
.
16
.
Rear
trailing
arms,
control
arms
and
final
drive
carrier
.
If
the
rear
brake
cine
is
disconnected
to
remove
a
trailing
arm,
the
complete
braking
system
must
be
bled
as
partof
the
installation
procedure
.
When
performing
repairs
to
rear
suspension
components,
refer
to
Fig
.
16
.
REAR
SUSPENSION
330-
9
0013112
REAR
SUSPENSION
ARMS
6
.
Disconnect
ABS
electrical
connectors
.
Label
and
then
disconnect
brake
lines
from
hydraulic
brake
unit
.
Plug
openíngs
.
See
Fig
.
12
.
~
~
A
1/
B
'1v
C
~
F
lu
11
-ri
J
.
0013244
A
.
Right
front
F
Front
from
master
cylinder
B
.
Leftfront
R
.
Rear
from
master
cylinder
C
.
Rear
Fig
.
12
.
Brake
fluid
linesat
ABS
hydraulic
unit
.
WARNING
-
"
On
cars
with
All
Season
Traction
(AST),
special
BMW
service
equipment
is
required
to
properly
bleed
the
Antilock
Brake
System
(ABS)
.
Removal
of
the
ABS
hydraulic
unit
is
not
recommended
un-
less
this
equipment
is
available
.
For
safetyrea-
sons,
the
brake
system
on
cars
with
ABS
must
not
be
bled
using
the
procedures
described
inthis
repair
group
.
"
Do
not
mix
up
the
fluid
fines
at
the
ABS
hydraulic
unit
Label
all
connections
before
disconnecting
.
7
.
Remove
ABS
hydraulic
unit
from
engine
compartment
.
8
.
Working
inside
car,
remove
panel(s)
frombeneath
steering
column
to
access
pedal
assembly
.
See513
In-
terior
Trim
.
12
.
Make
sure
al¡
nuts,
fluid
couplings,
thread
bores
and
mating
surfaces
are
clean
.
BRAKES
340-
9
0011261
Fig
.
13
.
Brake
pedal
clevispin
and
retaining
clip
(A)
.
Brake
booster
mounting
nuts
shown
at
arrows
.
13
.
If
necessary,
mount
master
cylinder
to
vacuum
booster
using
a
new
O-ríng
and
newself-locking
nuts
.
CAUTION-
Do
not
over-torque
the
master
cylinder
mounting
bolts
.
This
could
damage
the
brake
booster
and
prevent
proper
vacuum
build-up
.
14
.
Installation
is
reverse
of
Rmoval
.
"
Bleed
brakes
as
described
earlier
.
"
Check
and,
if
necessary,
adjust
brake
light
switch
above
brake
pedal
.
Tightening
Torques
"
Brakemaster
cylinder
to
brake
booster
...........
.
..
..
...
26
Nm
(18
ft-Ib)
"
Brake
booster
to
bulkhead
.
.
..
..
...
22
Nm
(16
ft-Ib)
"
Brake
fluidline
to
master
cylinder
or
ABS
hydraulic
unit
.......
.
..
17-19
Nm
(13-14
ft-lb)
9
.
Remove
clip
and
clevis
pin
from
brake
booster
pushrod
and
disconnect
it
from
brakepedal
.
Remove
brake
booster
mounting
nuts
.
See
Fig
.
13
.
NOTE-
10
.
Working
in
engine
compartment,
remove
brake
booster
When
replacing
the
brake
booster
one-way
valve
or
together
with
master
cylinder
.
vacuum
hose,
install
the
valve
so
that
the
molded
arrow
is
pointing
toward
the
intake
manifold
.
Use
new
hose
11
.
If
booster
or
master
cylinder
O-ring
is
being
replaced,
clamps
.
disconnect
master
cylinder
from
brake
booster
.
BRAKE
BOOSTER
9
.
Release
blower
motor
retaining
strap
andremove
blow-
er
motor
and
fans
fromcowl
opening
.
NOTE-
Twist
and
rotate
blowermotor
assembly
to
facilítate
re-
moval
from
opening
.
If
the
blower
motor
is
to
be
rein-stafled,
use
care
not
to
damage
fan
wheels
during
removal
.
ff
the
blower
motor
fs
to
be
replaced,
cut
offfan
wheels
at
center
to
aid
in
removal
.
10
.
Installation
is
reverse
of
removal
.
When
installing
a
re-
placement
blower
motor,
instan
motor
into
cowlarea
before
installing
fan
wheels
.
Blower
motor
test
specifi-
cations
are
listed
in
Table
a
.
NOTE
-
On
replacementblowermotors
from
BMW,
thefan
wheels
come
unattached
to
aid
in
installation
.
Locatearrow
on
blower
motor
and
instan
fan
wheels
atthis
po-
sition
.
Be
sure
color
coolng
matches
.
Retain
fan
wheels
using
the
new
clips
.
See
an
authorized
BMW
parts
de-
partment
for
the
latest
parts
information
.
Table
a
.
Blower
Motor
Test
Values
Testingvoltage
13
VDC
Operating
voltage
9-15
VDC
Max
.
current
consumption
(approx
.)
12
amps
Maximum
speed
3,600-4,000rpm
Axialplay
(max
.
allowable)
1
.0
mm
(0
.04
in
.)
Blower
motor
resistor
pack,
replacing
The
blower
resistor
pack
is
clipped
into
the
upper
left
side
of
theheater
box
.
1
.
Remove
lower
left
dash
trim
panel
.
See513
Interior
Trim
.
2
.
Working
under
left
(driver's)
side
of
dash,
unclip
and
pulí
out
resistor
pack
from
sideof
heater
box
.
Remove
harness
connector
from
resistor
pack
.
See
Fig
.
7
.
3
.
Installation
is
reverse
of
removal
.
Heater
valve,
replacing
The
two-way
heater
valve
is
located
in
the
rear
of
the
engine
compartment
on
the
driver
side
.
The
solenoid
operated
valves
control
the
coolant
flow
through
the
dual-chamber
heater
core
.
1
.
Drain
engine
coolant
.
See
170
Radiator
and
Cooling
System
.
HEATING
AND
AIR
CONDITIONING
640-
3
uuiGO4I
Fig
.
7
.
Blower
fan
resistor
pack
(black
arrow)
and
resistor
pack
re-
ceptacle
(white
arrow)
below
left
sideof
dash
.
WARNING
-
Allow
the
cooling
system
to
cool
before
opening
ordraining
the
cooling
system
.
2
.
Disconnect
hoses
and
harness
connector
at
heater
valve
.
See
Fig
.
8
.
001[ó38b
Fig
.
S
.
Hoses
(A)
and
harnessconnector
(B)
at
heatervalve
.
3
.
Carefully
pull
heater
valve
out
of
rubber
mounting
and
pull
up
and
out
of
engine
compartment
.
4
.
Installation
is
reverse
of
removal
.
Use
new
hose
clamps
.
Inspect
hoses
and
replace
asnecessary
.
HEATER
AND
CONTROLS