disconnecting battery BMW 328i 1998 E36 Owner's Manual

121-
8



BATTERY,
STARTER,
ALTERNATOR

1f
the
solenoid
audibly
cliicks
but
the
motor
does
not
turn,



Starter,
removing
and
installing
switch
on
the
lights
andtum
the
key
to
the
start
position
.
lf
the



(6-cylinder
engine
with
lights
go
out
while
attempting
to
start,
the
battery
cable
may
be



manual
transmission)
loose
or
the
starter
may
have
a
short
circuit
.
If
the
lights
stay

on,the
solenoid
is
most
likely
atfault
.
The
starter
on
a
6-cylinder
car
with
manual
transmission
is

Starter,
removing
and
installing

(4-cylinder
engine)



1
.
Disconnect
negative
(-)
battery
cable
.

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery

disconnection
cautions
given
at
the
front
of
this

manual
on
page
viii
.

2
.
Remove
guide
tube
for
oil
dipstick
.

3
.
Raise
vehicle
.

WARNING
-

Make
sure
the
car
ís
stable
and
wefl
supported
at
all
times
.
Use
a
professional
automotive
lift
or
jack
stands
designed
forthe
purpose
.
A
floor
jack
is
not
adequate
support
.

4
.
Disconnect
wiring
from
starter
.

5
.
Remove
top
and
bottom
starter
bolts
.
Bottom
bolt
must

be
removed
from
below
car
.
Remove
starter
support

bracket,
if
applicable
.

removed
from
below
.

2
.
Raise
vehicle
.

3
.
Remove
reinforcing
cross
bracefromunder
transmís-

sion,
if
applicable
.

4
.
Remove
cover
from
fuel
filter
and
fuel
lines
on
left
side

underneath
car,
if
applicable
.
Detach
fuel
lines
and
har-

ness
connectors
from
retainingbrackets,
as
necessary

5
.
Disconnect
wiring
from
starter
.

6
.
Loosen
andremove
bolts
and
nuts
fastening
starter
to

transmission
bell
housing
and/or
engine
block
.
Remove

starter
supportbracket
.

7
.
Remove
starter
from
below
.

8
.
Check
starter
pinion
gear
and
flywheel
teeth
for
dam-

age
.

9
.
Installation
is
reverse
of
removal
.

6
.
Pull
starter
downward
and
turn
until
solenoid
is
at
top,



Tightening
Torques

then
remove
from
car
.



"
Re¡
nforcing
cross
brace

to
chassis
(M10)
..
...............
42
Nm
(31
ft-Ib)

7
.
>Check
starter
pinion
gear
and
flywheel
teeth
for
dam-



"
Starter
to
engine
block
(M10
bolt)
...
50
Nm
(37
ft-Ib)

age
.



"
Support
bracket
to
starter
(M5
nut)
...
5
Nm
(44
in-lb)

"
Support
bracket

8
.
Installation
is
reverse
of
removal
.



to
engine
block
(M10
bolt)
.........
47
Nm
(35
ft-Ib)

"
Wire
to
terminal
50
(M6
nut)
.........
6
Nm
(53
ín-Ib)

"
Wire
to
terminal
30
(M8
nut)
.........
12
Nm
(9
ft-lb)

Tightening
Torques

"
Starter
to
engine
block
(M10
bolt)
...
50
Nm
(37
ft-lb)

Wire
to
terminal
50
(M6
nut)
........
6
Nm
(53
in-lb)

"
Wire
toterminal
30
(M8
nut)
...
,
..:.
12
Nm
(9
ft-Ib)

STARTER
SERVICE

The
fuel
injection
systems
used
on
the
1996
and
later
cars
covered
bythis
manual
are
OBD
II
compliant
.
This
system
is
in-
corporated
into
both
the
Bosch
M5
.2
(M44
engine)
and
the
Si-
emens
MS
41
.1
(M52/S52US
engine)
engine
management
systems
.
OBD
II
systems
use
sophisticateddiagnostic
soft-
ware
capable
of
recognizing
and
electronically
storing
hun-
dreds
of
DTCs
in
the
system
ECM
.
DTCs
can
only
be
accessed
using
special
scan
tooltest
equipment
.
The
BMW
dealer
is
equipped
with
the
specialized
OBD
II
scan
toolto
quickly
and
efficiently
locate
engine
management
problems
.
Alternately,
a
"generic"
scan
tool
can
be
used
to
access
OBD
II
fault
informa-
tion
.

NOTE-

"
At
the
time
this
manual
went
to
press,
generic
scan
tools
were
notwidely
available
for
BMW
vehicles
.
The
generic
sean
tool
is
a
specialized
toolthat
plugs
into
a
standardized
OBD
11
connector
on
1996
and
later
pas-senger
vehícles
built
for
sale
in
the
US
.

"
The
OBD
11
fault
memory
(including
an
illuminated
Check
Engine
light)
can
only
be
reset
using
the
spe-
cial
scan
tool
.
Removing
the
connector
trom
the
ECM
or
disconnecting
the
battery
will
not
erase
the
fault
memory
.

"
The
16-pin
OBD
11
diagnostic
connector
is
located
on
the
lower
left
dash
panel
.
Refer
to
Fig
.
1
.

6

1
.
Secondary
air
pump
2
.
Electric
solenoid
valve
3
.
One-way
check
valve
4
.
Intake
manifold
5
.
Exhaust
manifolds
6
.
Secondary
air
check-valve

®
G~



i

o
o



0
0
G
0000
o



,-
00

~

1111111
in

,,
0
1--

a

Fig
.
5
.



Components
of
6-cylinder
secondary
air
injection
system
.
4-
cylinder
system
is
similar
.

Secondary
AirInjection

FUEL
INJECTION



130-
5

All
OBD
II
6-cylinder
engines
are
equípped
with
asecond-
ary
air
injection
system
.
In
addition,
beginning
in
January
1997,
the
M44
engine
was
classified
as
a
TLEV
(Transitional
Low
Emission
Vehicle)
engine
and
is
also
equipped
with
sec-
ondary
air
injection
.

Typical
components
of
the
secondary
air
injection
system

are
depicted
in
Fig
.
5
.

Secondary
air
injection
usesan
electric
pump
to
pump
fresh
air
finto
the
exhaust
systemupstream
of
the
catalytic
converter
during
engine
warm-up
.
By
providing
extra
oxygen
to
the
un-
burned
fuel
in
the
exhaust,
hydrocarbons
oxidize
and
carbon

monoxide
combines
with
oxygen
to
form
carbon
dioxide
andwa-
ter
.
The
air
injection
pump
stops
within
a
specified
timed
intenral
.

4

0013120

GENERAL

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
.

Oxygen
Sensor
FUEL
DELIVERY
TESTS
FUEL
INJECTION



130-
9

"
Voltage
at
¡dle
..
.
..
..
....
0
.2
to
0
.8
VDC,
fluctuating



Checking
fuel
delivery
is
afundamental
part
of
trouble-
shooting
and
diagnosing
the
engine
management
system
.
Fuel
pressure
directly
influences
fuel
delivery
.
An
accurate

NOTE-



fuel
pressure
gauge
will
be
needed
to
make
the
tests
.

To
check
sensorresponse
to
lean
and
rich
mixtures,
createenairleak,
orpull
vacuumhoseofffue¡
pressure



There
are
three
significant
fuel
delivery
values
to
be
mea-

regulator
to
increase
fuel
pressure
.



sured
:

3
.
Separate
sensorharness
connector
from
sensor
.
Check

for
battery
voltage
between
terminals
3
and
4
(green

wire
and
brown
wire)
in
main
wiring
harness
side
of
con-

nector
with
engine
running
.
If
voltage
is
not
present,

check
oxygen
sensor
heater
relay
.
See610
Electrical

Component
Locations
.

4
.
Check
heater
element
resistance
between
terminals
3
and
4
in
sensor
side
of
connector
.
If
element
is
electri-

cally
open
(no
continuity),
replace
sensor
.

NOTE-

The
oxygen
sensor
heater
relay
is
mounted
in
the
main
power
distributfon
box
in
the
left
rear
of
the
engine
com-
partment
.
Refer
to
Fig
.
6
.
The
heater
relay
is
energized
wíth
positive
(+)
battery
voltage
from
the
main
relayanda
switched
ground
from
the
ECM
.
See
Electrical
Wir-
ing
Diagrams
.

"
Oxygen
sensor
to
exhaust
pipe
...
..
55
Nm
(41
ft-Ib)

"
System
pressure-created
by
the
fuel
pump
and
main-
tained
by
the
pressure
regulator
.

"
Fuel
delivery
volume-created
by
the
fuel
pump
and
af-
fected
by
restrictions,
suchasclogged
fuel
filter
.

"
Residual
pressure-the
pressure
maintained
in
the
closed
system
after
the
engine
and
fuel
pump
are
shut

off
.

Procedures
for
measuring
the
first
two
quantities
arede-
scribed
in
160
Fuel
Tank
and
Fuel
Pump
.
Residual
fuel
pres-
sure
is
checked
using
the
procedure
detailed
later
in
this

group
.

Operating
fuel
pump
fortests

To
operate
the
fuel
pump
for
testing
purposes
without
hav-

íng
to
runthe
engine,
the
fuel
pump
relay
can
be
bypassed
to

power
the
pump
directly
.
Fuel
pump
relay
location
is
shown
in

Fig
.
6
.

5
.
¡f
oxygen
sensor
doesn't
produce
a
fluctuating
voltage



To
runthe
fuel
pump,
remove
the
fuel
pump
relay
and
con-
and
preheater
circuit
is
OK,
replace
sensor
.



nect
the
socket
for
relayterminal
30
to
the
socket
for
relay
ter-

mina¡
87
with
a
fused
jumper
wire
.
After
completing
the
tests,

NOTE-



remove
the
jumper
wire
.

If
not
already
applied,
coat
the
oxygen
sensor
threads
with
an
anti-seize
compound
before
installation
.
Do
not



CAUTION-
getthe
compound
on
the
sensor
tip
.
"
Relay
locations
may
vary
.
Use
care
when
identi-
fying
relays
and
making
electrical
checks
at
the
fuselrelay
panel
.
See
610
Electrical
Compo

Tightening
Torque



nent
Locations
for
additional
relay
information
.

"
The
fuel
pump
relay
has
a
1
.5
mm2
red
wire
at
ter-
minal
30
in
the
relay
socket
.
Terminal
87
has
a
1
.5
mm
2
greenlviolet
wire
.
See
Electrical
Wiring
Di-
agrams
for
additional
wiring
information
.

NOTE-

Thejumper
wire
should
be
1.5
mm2
(14
ga
.)
and
in-
clude
an
in-line
tuse
holder
with
a15
amp
tuse
.
To
avoid
fuselrelay
panel
damage
from
repeated
connect-
ing
and
disconnecting,
also
include
a
toggle
switch
.
A
heavy-duty
jumper,
BMW
tool
no
.
61
3
050,
is
also
available
from
an
authorized
BMW
dealer
.

FUEL
DELIVERYTESTS

130-
1
6



FUEL
INJECTION

Throttie
position
sensor
(TPS),



Idie
speed
control
valve,
testing
and
replacing



testing
and
replacing

The
throttie
position
sensor
(TPS)
is
mounted
on
the
side
of



¡die
speed
is
maintained
by
the
ECM
via
the
¡die
speed
con-

the
throttie
housing
and
is
directly
connected
to
the
throttie



trol
valve
.
See
Fig
.
24
.
¡die
speed
is
adaptive
through
the
valve
shaft
.
The
ECM
sends
a
voltage
signal
to
the
potentiom-



ECM
and
no
¡die
speed
adjustments
can
be
made
.
Before
eter-type
sensor
and
monitors
the
voltage
that
comes
back
.



testing
the
valve,
confirm
that
the
throttie
position
sensor(TPS)
is
working
correctly
.

Check
TPS
function
by
disconnecting
the
harnessconnec-

tor
and
checking
reference
voltage
and
sensor
resistance
.

See
Table
e
and
Fig
.
23
.
If
voltage
is
not
present,
check
the

output
voltage
signal
from
the
ECM
and
check
the
wiring
be-
tween
the
sensor
and
the
ECM
.
If
the
sensor
resistance
is
in-
correct,
replace
the
throttie
position
sensor
.

NOTE
-

The
throttie
position
sensor
is
not
adjustable
.
If
test
re-
sults
are
íncorrect,
the
sensor
should
be
replaced
.

Table
e
.
Throttle
Position
Sensor
Tests

(DME
1
.7)

Testconditions



1
Terminais



1
Test
value

Harness
connec-



(
1
and
ground
in



15
VDC
(approx
.)
tor
disconnected,



harness
connector
ignition
on

0013235

Fig
.
23
.
Throttieposition
sensor
terminal
identification
on
M42
engine
.

Harnessconnec-



I
1
and
3
at
sensor



(
4k
ohms
(approx
.)
tor
disconnected,



terminais
ignition
off
Connector
dis-



1
and
2
at
sensor



Continuously
vari-
connected,
igni-



terminais



able
from
1-4
k
tion
off
.
Throttle



ohms
(approx
.)
with
rotated
from
¡die



out
interruption
to
fui]
position

BOSCH
DME
Ml
.
7
COMPONENT
TESTS
AND
REPAIRS

Fig
.
24
.
¡die
speed
control
valve
(arrow)
on
M42
engine
.

NOTE
-

"
The
tests
given
below
are
electrical
checks
only
.
They
do
not
check
the
mechanical
operation
of
the
valve
or
if
the
valve
is
sticking
or
worn
.
If
the
valve
is
suspect,
substituting
a
known
good
valve
is
the
best
way
to
check
for
amechanical
fault
.

1
.
Check
battery
(+)
voltage
to
valve
:

0013226

"
Disconnect
harness
connector
from
valve
.
"
Check
for
battery
voltage
at
terminal
2
(red/white
wire)
.
"
If
voltage
is
not
present
check
wiring
between
valve
and
main
relay
(terminal
87)
.

2
.
Check
that
ECM
signal
is
reaching
valve
:

"
With
engine
running,
check
that
¡die
speed
control
valve
is
audibly
buzzing
.
"
If
valve
is
not
working,
disconnect
wiring
harness
con-
nector
.

"
Connect
12V
probe
light
across
connector
terminais
.
"
Turn
ignition
key
on
;
probe
should
light
.
lf
probe
does
nof
light,
check
the
wiring
from
the
ECM
(pin
29)
to
the
valve
.
See
Table
h
.
lf
probe
does
light
but
¡die
quality
is
poor,
the
valve
is
most
likely
sticking
and
or
worn
and
should
be
replaced
.

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

001ía4
i

Fig
.
34
.
Intake
air
temperature
(IAT)
sensor
in
top
section
of
air
filter
housing
.

¡die
speed
control
valve,
replacing

side
of
the
throttle
body
.
See
Fig
.
35
.

1
.
Disconnect
harness
connector
from
¡die
valve
.

0012725

Fig
.
35
.
M44
engine
:
Throttle
housing
showing
(A)
throttle
position
sensor
(fPS)
and
(B)
¡die
speed
control
valve
.

2
.
Remove
twomountingscrews
holding
sensor
to
throttle

housing
.

The
¡die
speed
valve
on
the
M44
engine
is
located
on
the

FUEL
INJECTION



130-23

2
.
Disconnect
vacuum
hose
and
retaining
screws
.

3
.
Pull
¡die
speed
control
valve
from
its
fittings
.

4
.
Installation
is
reverse
of
rémoval
.
Always
replace
0-

rings
and
seals
.

NOTE

Poor
driveability
may
be
notíced
after
installing
a
re-
placement
¡dio
control
valve
.
After
about10
minutes
of
driving,
the
idie
speed
should
retum
to
normal
.

SIEMENS
MS
41
.1

COMPONENT
REPLACEMENT

On-Board
Diagnostics
II
(OBD
II)
is
incorporated
into
the
Si-

emens
MS
41
.1
engine
management
systems
used
in
the

M52
and
S52US
engine
.
Refer
to
Fig
.
36
.

OBD
11
is
capable
of
detecting
a
fui¡
range
offaults
.
When

faults
are
detected,
a
Diagnostic
Trouble
Code
(DTC)
is

stored
in
the
system
ECM
.
The
Check
Engine
warning
light
will
also
come
on
if
an
emissions-related
fault
is
detected
.
The

most
efficient
way
to
diagnose
the
Siemens
OBD
II
system
is

by
using
a
specialized
scan
tool
.
The
OBD
II
system
is
capa-

ble
of
storing
hundreds
of
faults,
making
diagnostics
with
a
scan
tool
the
only
viable
method
.
Therefore,
system
diagnos-

tics
is
not
covered
here
.

NOTE
-

"
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
disconnecting
the
battery
will
not
erase
the
fault
memory
.

"
The
16-pin
OBD
11
diagnostic
connector
is
located
on

the
lower
left
dash
panel
.
Refer
to
Fig
.
1
.

"
BMW
special
scan
tool
ora
"generic"
OBD
11scan
tool

must
be
used
to
access
DTCs
.
3
.
Installation
is
reverse
of
removal
.
No
adjustment
is
nec
essary
.



"
Table
1
lists
engine
control
module
(ECM)
pinouts
forthe
MS
41
.1
systems
.

SIEMENS
MS
41
.
1
COMPONENT
REPLACEMENT

130-26



FUEL
INJECTION

Throttle
position
sensor
(TPS),
replacing

The
throttie
position
sensor
is
located
on
the
side
of
the
throttie
housing
.
See
Fig
.
40
.

Fig
.
40
.
M52
engine
:
Throttle
position
sensor
(arrow)
.

1
.
Unplug
harness
connector
from
sensor
.

NOTE
-

On
cars
with
tractioncontrol,
do
not
confuse
the
throttieposition
sensor
on
the
main
throttie
body
wíth
the
throt-
tie
position
switch
on
the
secondary
throttie
body,
where
applicable
.

3
.
Installation
is
reverse
of
removal
.

¡die
speed
control
valve,
replacing

0012700b

The
¡die
speed
control
valve
is
mounted
on
the
underside
of
the
intake
manifoldadjacent
to
the
dipstick
tube
bracket
.
Ac-
cessing
the
valve
is
best
accomplished
by
first
removing
the
throttie
housing
.

1
.
Disconnect
intake
air
bootfrom
throttie
housing
.
Unbolt
throttie
body
and
¡ay
aside
.
(Do
not
disconnect
throttie
cable
or
electrical
harness
connectors
to
throttie
body
.)

2
.
Unbolt
dipstick
tube
bracket
from
intakemanifold
.

3
.
Workíng
under
intake
manifold,
disconnect
electrical
harness
connector
from
¡die
speed
control
valve
.

4
.
Remove
two
bolts
retaining
¡die
speed
control
valve
to
underside
of
intake
manifold
.
Remove
valve
from
intake
manifold
.
Remove
hose
clamp
and
disconnect
hose
.

ECM
PIN
ASSIGNMENTS

mately
one
minute
.

Vacuum
seal

Mounting
bracket

Electrical
connector

0013185

Fig
.
41
.
M52
engine
:
¡die
speed
control
valve
(located
under
intake
manifold)
.

5
.
Installation
ís
reverse
of
removal
.
Use
new
gaskets
when
installing
.

NOTE
-

Poor
driveabilíty
may
be
noticed
atter
installing
a
re-
placement
idle
speed
control
valve
.
After
about
10
min-utes
of
dríving
the
idle
speed
should
return
to
normal
.

ECM
PIN
ASSIGNMENTS

2
.
Remove
twomountingscrews
holding
sensor
to
throttie
housing
.



Engine
control
module
(ECM),
accessing

1
.
Disconnect
negative
(-)
battery
cable
.
Wait
approxi-

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
vüi
.

2
.
Remove
engine
control
module
(ECM)
compartment
cover
from
right
side
of
engine
compartment
rear
bulk-
head
.
Cover
is
retained
withfour
captíve
screws
.
See
Fig
.
42
.

3
.
Disconnect
control
module
harness
connector
by
re-
leasing
fastener
and
pivoting
connectorup
and
off
ECM
.

4
.
Remove
ECM
from
retaining
brackets
and
pull
ECM
from
its
holder
.

5
.
Installation
is
reverse
of
removal
.

160
Fuel
Tank
and
Fuel
Pump

GENERAL
.
.
.
.
.
.
...........
.
....
.
.
.
.
.
.
160-1



Operating
fuel
pump
for
tests
.
.
.
.
.
.
.......
.160-6

Fuel
Pump
Electrical
Tests
.
.
.
.
.
.
.
...
.
.
.
.
.
160-7

FUEL
TANK
AND
LINES
..
.
.
.
..........
160-2



Fuel
pump
electrical
circuit,
testing.
...
.
.
.
.
.
160-7

Fuel
tank,
draining
..
.
.
.
.
.
.
.
.
.
..........
160-2



Fuel
pump
power
consumption,
testing
.
.
.
.
.
.
160-7

Fuel
tank,
removing
and
installing
.........
160-3



Fuel
Delivery
Tests
....
.
.
.
...
.
.....
.
.
.
..
160-8

Fuel
Tank
Evaporative
Control
System
.....
160-4



Relieving
fuel
pressure
and
connecting

fuel
pressure
gauge
..
.
...........
.
.
.
..
160-8

FUEL
LEVEL
SENDERS
.
.
.
.
.
.......
.
.
.
160-4



System
pressure,
testing
.................
160-9

Fuel
level
senders,
testing
.
.
.
.
.
.......
.
.
.
160-5



Fuel
delivery
volume,
testing
.............
160-10

Fuel
leve¡
sender
and
fuel
pump
(right
side),
emoving
and
installing
.
.
.
.
.
.
160-5



TABLES

Fuel
leve¡
sender
(left
side),



a
.
FuelLeve¡
Sender
Resistances
...........
.
.
..
.160-5

removing
and
installing
.........
.
.
.
.
.
.
.
160-6



b
.
Fuel
Pump
Current
...
.................
..
...
160-8

c
.
Fuel
Pressure
Specifications
..............
.
..
160-10

FUEL
PUMP
.
.
.
................
.
.
.
.
.
.
.
160-6



d
.
Fuel
Pump
Delivery
Specifications
.........
.
..
160-10

Fuel
Pump
Fuse
and
Relay
.
.
.
....
.
.
.
.
.
.
.
160-6

GENERAL

This
repair
group
covers
service
information
specifically
for



The
cautions
and
warnings
on
this
page
should
beob
the
fuel
supply
system
.
Information
on
the
fue¡
injection
sys-



served
when
servicing
the
fuel
system
.
tem
is
covered
in
130
Fuel
Injection
.

NOTE-

Fue¡
filter
replacement
is
covered
in
020
Maintenance
Program
.

WARNING
-

"
The
fuel
system
is
designed
to
retain
pressure
even
when
the
ignition
isoff
.
When
working
with
the
fuel
system,
loosen
the
fuel
lines
slowly
toal-
low
residual
fuel
pressure
to
dissipate
gradually
.
Avoid
spraying
fuel
.

"
Before
beginning
any
work
on
the
fuel
system,
place
a
tire
extinguisher
in
the
vicinity
of
the
work
area
.

"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
work
near
heaters
or
other
tire
hazards
.

"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
fines
.

"
Do
not
use
a
work
light
near
any
fuel
.
Fuel
may
spray
onto
the
hot
bulb
causing
a
tire
.

"
Make
sure
the
work
area
is
properly
ventifated
.

FUEL
TANK
AND
FUEL
PUMP



160-1

CAUTION-

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

"
Before
making
any
electrical
tests
with
the
ignition
tumed
on,
disable
the
ignition
system
as
de-
scribed
in
120
Ignition
System
.
Be
sure
the
bat-tery
is
disconnected
when
replacing
components
.

"
To
prevent
damage
to
the
ignition
system
or
the
electronic
fuel
system
components,
including
the
control
unit,
aiways
connect
and
disconnect
wires
and
test
equipment
with
the
ignition
off
.

"
Cleanliness
is
essential
when
working
with
the
fuel
system
.
Thoroughly
clean
the
fuel
fine
unionsbefore
disconnecting
any
of
the
fines
.

"
Use
only
clean
tools
.
Keep
removed
parts
clean
and
sealed
or
covered
with
a
clean,
lint-free
cloth,
especially
if
completion
of
the
repair
is
delayed
.

"
Do
not
move
the
car
while
the
fuel
system
is
open
.

"
Avoid
using
high
pressure
compressed
air
to
blow
out
fines
and
componente
.
High
pressure
can
rupture
infernal
seals
and
gaskets
.

"
Always
replace
seals
and
O-rings
.

GENERAL

Fuel
leve¡
senders,
testing



Fuel
leve¡
sender
(right
side)

The
left
and
right
fuelleve¡
sending
units
are
wired
in
series
.



and
fuel
pump,
removing
and
installing

The
fuel
gauge
receives
a
signal
that
is
the
average
of
the
two



1
.
Disconnect
negative
(-)
cable
from
battery
.

input
values
.

1
.
Remove
rear
seat
cushion,
lift
up
insulation
mats,
andremove
both
fuel
tank
access
covers
.

2
.
Disconnect
white
plug
on
each
sending
unit
.
See
Fig
.
6
.

3
.
Check
resistance
value
of
eachsending
unit
.
Values
should
be
the
same
.

5
.
If
valuesare
different,
remove
sending
units
as
described

below,
and
check
resistance
valuésacross
terminals
.
Table
a

lists
resistance
values
for
senders
at
various
float
positions
.

Table
a
.
Fuel
Leve¡
Sender
Resistances

Float
position



Test
result
(ohms)

Right
side
empty



10
ohm
t2

Right
side
full



250
ohm
±
5
Left
side
empty



10
ohm
t
2

Left
side
fui¡



250
ohm
±
5

FUEL
TANK
AND
FUEL
PUMP



160-
5

CAUTION
-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautionsglven
at
the
front
of
this
manual
onpage
viii
.

2
.
Drain
fuel
from
tank
as
described
earlier
.

WARNING
-

Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
fines
.

3
.
Remove
rear
seat
cushion
and
pull
back
insulation
pad
under
right
side
.

4
.
Remove
screws
holding
rightfuel
tank
accesscover
.

Remove
cover
.

5
.
Label
fuel
hoses
.
Disconnect
hoses
and
harness
con-

nectors
from
fuel
sending
unit
and
fuel
pump
.

6
.
Unscrew
threaded
collar
from
fuel
pumplfuel
leve¡
sender
.
Slowly
withdraw
assembly
from
tank,allowing

fuelto
drain
off
.
See
Fig
.
7
.
0013187
&
0013194

Fig
.
6
.



Fuel
pump/leve¡
sender
terminal
identification
.
Check
resis-
tance
at
terminals
of
white
connectors
(arrows)
.



"
If
necessary,
push
leve¡
sender
arm
toward
fuel
pump

assembly
to
facilitate
removal
.

NOTE
-

BMW
special
tool
no
.
16
1
020
should
beused
to
re-
move
and
install
the
threaded
collar
.
Damage
to
the
collar
may
result
if
the
special
tool
is
not
used

WARNING
-

NOTE-



Fuel
may
be
spilled
.
Do
not
smoke
or
work
near

The
compensating
siphon
pump
(Fig
.
1)
maintains
the



heaters
or
other
fire
hazards
.

fuel
leve¡
between
the
right
and
left
tank
lobes
.
If
the
re-
sistances
are
different
between
the
left
and
right
send-
ers,
remove
the
senders
and
visually
inspect
the
leve)
in



7
.
Using
a
new
sealing
ring,
install
pump
and
sending
each
lobe
.
If
the
leve¡
is
different,
check
the
siphon
com-



unit,
being
sure
that
fuel
line
connections
point
in
same

pensating
pump
.



direction
as
they
carne
out
.

8
.
Reconnect
harnessconnector
and
hoses
.
Fill
tank
and

check
for
leaks
by
running
engine
.
Insta¡¡
access
cover

and
its
mountingscrews
.
Reconnect
negative
(-)
cable

to
battery
.

CAUTION
-

Before
starting
the
engine,
fill
the
fuel
tank
with
at
least
1
.5
gallons
(5liters)
of
fuel
.
The
pump
will
be
damaged
if
you
run
it
without
fuel
.

FUEL
LEVEL
SENDERS