Engine wire harness BMW 328i 1997 E36 User Guide

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

113-12



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

18
.
Working
from
underside
of
intake
manifold,
disconnect



21
.
Detach
oil
dipstick
guide
tube
from
manifold
.
Disconharness
connectors,
vent
hoses,
and
air
bypass



nectvent
hose
at
base
of
dipstick
.
hoses)
.

22
.
Remove
intake
manifold
from
engine
byremoving
sev-19
.
Working
at
rear
of
intake
manifold,
label
and
disconnect



en
mounting
nuts
from
above
andtwo
support
bracket
fuel
supply
and
fuel
return
lines
.
Remove
fuelline
hold



bolts
from
below
.
See
Fig
.
32
.
down
bracket
to
free
lines
.
See
Fig
.
31
.

NOTE-

On
M52IS52US
engines,
a
special
fitting
is
used
to
re-tain
the
fuel
fines
to
the
fuel
rail
.
Use
BMW
special
tool
no
.
16
1
050
to
expand
the
locking
clip
inside
the
end
of
the
fuellíne
fittings
.

WARNING
-

"
The
fuel
system
is
desígned
to
retan
pressure
even
wheh
the
ignition
is
off
.
When
working
with
the
fuel
system,
loosen
the
fuel
lines
slowly
toal-
low
residual
fuel
pressure
to
dissipate
gradually
.
Avoid
spraying
fuel
.

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

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

20
.
Remove
mountingscrews
and
release
wiring
harness
duct
at
rear
bulkhead
and
move
aside
.
Remove
wiring
harness
brackets
frombulkhead
.

CYLINDER
HEAD,
6-CYLINDER

Fig
.
32
.
Intake
manifoldnuts
and
support
bracket
bolts
(arrows)
.

CAUTION-

Stuff
clean
rags
into
the
open
intake
ports
topre-
001269s



vent
any
ports
from
falfing
into
the
engine
.
Fig
.
31
.
Fuel
lines
at
intake
manifold
on
M52/S52
engine
.
Use
BMW
special
tool
16
1
050
to
release
locking
fittings
at
ends
of
fuel
enes
.



1



Timing
chains,
uncoupling

23
.
Remove
VANOS
unit
from
frontof
cylinder
head
.
See
VANOS
section
in
117
Camshaft
Timing
Chain
.

24
.
Setengine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
Arrows
on
camshaft
sprockets
should
be
pointing
up
.

NOTE-

To
confirm
that
the
crankshaft
is
set
to
the
TDC
posi-
tion,
check
that
the
OIT
mark
(0°
TDC)on
the
front
low-
er
timing
chain
cover
ís
aligned
with
the
víbration
damperSee
Fig
.
33
.

25
.
Lock
crankshaft
at
TDC
.

"
Insert
BMW
special
tool
no
.
11
2
300
through
transmis-
sion
bellhousing
and
finto
hole
in
flywheelor
drive
plate
.
See
Fig
.
34
.

113-
1
8



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

CYLINDER
HEAD,
6-CYLINDER

Fig
.
46
.
Primary
chaintensioner
being
installed
.
Piston
cutout
must
engage
chain
rail
.

22
.
Install
intake
cam
cover
and
then
install
cylinder
head

cover
.
Check
for
correct
seating
of
half-moons
in
back

of
cylinder
head
cover
.
Use
a
small
amount
of
3-Bond
O

1209
orequivalent
seaiant
at
corners
of
half-moon
cut-

outs
.

23
.
Install
front
exhaust
pipes
to
manifolds
using
new
gas-
kets
and
nuts
.
Coat
manifold
studs
with
copper
paste
prior
to
installing
nuts
.

24
.
Installationof
remaining
parts
is
reverse
of
removal
.

Refill
cooling
system
as
described
in
170
Radiator
and

Cooling
System
.
Change
engine
oil
and
filter
as
de

scribed
in
020
Maintenance
Program
.
Check
adjust-

ment
of
accelerator
cable
.
Additional
tightening
torques

are
given
below
.
Reconnect
battery
last
.

25
.
Installationof
remaining
parts
is
reverse
of
removal,

noting
the
following
:

"
Make
sure
all
sealing
surfaces
are
clean
and
free
of
old

gasket
material
.
Insta¡¡
new
intake
manifold
gasket
.

"
Reinstall
harness
connectors
for
oil
pressure
switch

and
coolant
temperature
sensor
before
installing
in-

take
manifold
.

"
Refill
cooling
systemas
described
in
170
Radiator

and
Cooling
System
.

"
Change
engine
oil
and
filter
as
described
in
020
Main-

tenance
Program
.

"
If
necessary,
adjust
accelerator
cable
.

"
Reconnect
battery
last
.

CAUTION-

To
prevent
damaging
engine
electronic
systems,
be
sure
to
install
all
ground
wirespreviously
re-
moved,
including
the
ground
wires
at
the
cylinder
head
for
the
ignition
coils
.

Tightening
Torque



Tightening
Torques

"
Cylinder
head
cover



"
Coglant
drain
plug
to
cylinder
block
.
.
25
Nm
(18
ft-Ib)

to
cylinder
head(M6
screws)
.
.
.....
10
Nm
(89
in-lb)



"
Intake
manifold
to
cylinder
head
.
...
.
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)

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
.

117-
1
8



CAMSHAFT
TIMING
CHAIN

CAUTION-

It
is
crítical
that
the
exhaustcamshaft
sprocket
be

turned
only
the
mínimum
amount
necessary
to

engage
the
gear
cup
.
If
this
procedure
is
done
ín-
correctly,
the
VANOS
system
may
not
function

throughout
íts
full
range
.

NOTE-

As
the
control
unit
isinstalled,
the
secondary
sprockets
will
rotate
in
the
counterclockwise
direction
.
It
may
be

necessary
to
guide
sprockets
counterclockwise
as
the

control
unit
is
installed
.

8
.
On
cars
built
from3/95
:
Use
a
spanner
tool
(See
Fig
.

39
.),
turn
exhaust
sprocket
counterclockwise
(as

víewed
from
front
of
engine)
only
enough
to
mesh

gear
cup
splines
with
camshaftgear
.
Slowly
push

VANOS
control
unit
towards
camshaft
until
it
is
fully

seated,guiding
chains
in
counterclockwise
direction
.

CA
UTION-

Ensure
that
the
first
available
tooth
engages
.

9
.
Install
and
tightencontrol
unit
nuts
and
bolt
.

10
.
Connect
harness
connector
to
VANOS
solenoid
.
Using

new
seals,
insta¡¡
oil
line
fitting
.

Tightening
Torques

"
VANOS
control
unitto
cylinder
head

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

M8
bolt
.....
.
.
.
.
..
.............
22
Nm
(17
ft-Ib)

"
VANOS
oil
supply
line
to
control
unit
.
32
Nm
(24
ft-Ib)

11
.
Slowlyunlock
and
release
secondary
chain
tensioner
.

12
.
Preloadprimary
chain
by
tightening
BMW
special
tool

no
.
112
240
(dummy
chain
tensioner)
to
1
.3
Nm
(11
in-
lb)
.
Then
tighten
exhaust
camshaft
sprocket
mounting

bolts
alternately
in
two
stages
.

Tightening
Torque

"
Secondarytiming
chain
sprockets
to
camshafts

(Tora
boits)

Stage
1
..
...............
...
.
.
...
5
Nm
(44
in-lb)

Stage
2
..
...............
...
.
.
..
22
Nm
(17
ft-Ib)

VANOS
(VARIABLE
VALVE
TIMING)

13
.
Remove
flywheel
locking
tool
from
transmission
bell-

housing
.
Remove
camshaft
locking
tool
from
rear
of

cylinder
head
.

14
.
Turn
engine
over
by
hand
at
least
two
fui¡
crankshaft
ro-

tations
.
Reinstall
camshaft
locking
tool
and
flywheel

locking
toolto
make
sure
all
adjustments
are
correct
.
If

settings
are
correct,
remove
locking
tools
.

15
.
Remove
BMW
special
tool
112
420
(dummy
chain
ten-
sioner)
from
side
of
cylinder
head
.
Install
primary
chain

tensioner
so
that
cutout
in
tensioner
piston
engages

chain
rail
.
See
Fig
.
34
.
Using
new
seals,
install
and

tighten
access
plugs
in
VANOS
control
unit
.

Tightening
Torque

"
Access
plugs
to

VANOS
control
unit
.
..
.
.....
.
..
...
50
Nm
(37
ft-lb)

"
Primary
timing
chain
tensioner
plug
to
tensioner
sleeve

M50/S50USengine
.
.
..
.
.
...
.
...
..
50
Nm
(37
ft-Ib)

M52/S52US
engine
...
..
...
...
...
40
Nm
(30
ft-Ib)

16
.
Install
oil
baffle
cover
above
intake
camshaft
.
Install

three
cylinder
head
covermounting
studs
to
rear
of

head
.
Instali
cylinder
head
cover
.

Tightening
Torque

"
Cylinder
head
cover

to
cylinder
head
(M6
screws)
......



10
Nm
(89
in-Ib)

17
.
Installationof
remaining
parts
is
reverse
of
removal
.

NOTE-

Be
sure
to
install
the
ground
wíres
at
the
cylinder
head
cover
mounting
studs
and
at
the
front
of
the
cylinder
head,
if
applicable
.

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

120-
4



IGNITION
SYSTEM

2
.
Check
for
battery
voltage
o
cofs
.
If
voltage
is
not



Table
b
.
Ignition
Coil
Resistance

present,
check
wire
between
terminal
15
and
ignition



(M42
Engine)
switch
.
See
Electrical
Wiring
Diagrams
.

"
On
M42
engine,
connect
digital
multimeter
between
ter-

minal
15(+)
in
each
harness
connector
and
ground
.
See

Fig
.
4
.

"
On
M44
engine,
connect
voltmeter
between
terminal
2

(15+)
in
connector
and
ground
.
Turn
ignition
on
and

check
for
voltage
.
See
Fig
.
5
.

3
.
Turn
ignition
off
.

0
4a15

Fig
.
4
.



Ignition
coil
harness
connector
terminal
identification
for
M42

engine
.

Fig
.
5
.



Ignition
coil
harness
connector
terminal
identification
for
M44
engine
.

CAUTION-

The
wiring
to
the
coil(via
the
ignition
switch
15+)
is
not
fuse
protected
.
Use
care
when
testing
thiscircuit
.

4
.
Use
a
digital
multimeter
totest
coil
primary
resistance
.

"
On
M42
engine,
use
Table
b
asa
guide
to
check
coil

resistance
.
Make
checks
at
each
harness
connector
.

"
On
M44
engine,
use
Table,c
as
a
guide
to
check
coil
primary
resistance
.

5
.
Inspect
coil
housing
for
hairline
cracks
or
leaking
cast-
ing
material
.
See
Fig
.
7
.
A
leaky
ignition
coil
may
indi-



11502

cate
a
faulty
ECM
(engine
control
module)
.
Check
the
ECM
before
installing
a
new
coil
.



Fig
.
6
.



Ignition
coil
harnessconnector
terminal
identification
for
6-
cylinder
engine
.

IGNITION
SYSTEM
SERVICE

11502

Terminals
Resistance
(refer
to
Fig
.
4
.)

Coil
primary



1
(-)
and
15
(+)



10
.4-0
.8
ohms

Coil
secondary



N
.A
.



N
.A
.

Table
c
.
Ignition
Coil
Resistance

(M44
Engine)

Terminais
Resistance
(referto
Fig
.
5
.)

Coil
#1
primary



1
(-)
and
2
(+)



0
.4-0
.8
ohms

Coil
#2
primary



6
(-)
and2
(+)



0
.4-0
.8
ohms

Coil
#3
primary



7
(-)
and
2
(+)



0
.4-0
.8
ohms

Coil
#4
primary



5
(-)
and2
(+)



0
.4-0
.8
ohms

Coil
secondary



N
.A
.



N
.A
.

NOTE-

If
a
single
coilís
faulty
on
M44
engines,
the
complete
coil
pack
will
have
to
be
replaced
.

Ignition
coil,
testing
and
replacing

(6-cylinder
engine)

CAUTION-

Use
a
digital
multimeter
for
the
following
tests
.

1.
Remove
plastic
enginecovers
from
top
of
engine
by

prying
off
nut
covers
and
removingcover
mounting

nuts
.
See
113
Cylinder
HeadRemoval
and
Installa-

tion
.

2
.
Disconnect
harnessconnectorfromcof
.
Connect
mul-
timeter
between
terminal
15
(+)
in
connector
and

ground
.
See
Fig
.
6
.

3
.
Turn
ignition
on
and
check
for
batteryvoltage
.

"
If
batteryvoltage
is
not
present,
check
wire
between

terminal
15
and
ignition
switch
.
See
Electrical
Wiring

Diagrams
.

"mozo

120-
6



IGNITION
SYSTEM

Crankshaft
position/rpm
sensor,

testing
and
replacing
(front
mounted)

1
.
Disconnect
sensor
harness
connector
.

2
.
Using
a
digital
multimeter,
check
resistance
between
terminals
1
and
2
in
connector
.
See
Fig
.
10
.

n1
n2n3

Fig
.
10
.
Crankshaft
position/rpm
sensorconnector
.

Crankshaft
positionlrpm
sensor
specifications

"
Coil
resistance
(approx
.)
terminais
1
and
2
....
.
..
...
....
1280
±
10%
ohms

"
Air
gap
(sensor
distance
from
toothed
wheel)
..
.
.
........
.1
.0
±
0
.3
mm
(0
.04
±
0
.01
in
.)

3
.
If
the
resistance
is
not
correct,
the
sensor
is
faulty
and
should
be
replaced
.

NOTE
-

When
installing
the
new
sensor,
be
sure
thewiring
Is
rerouted
in
the
same
orientation
.
Secure
the
sensor
us-
ing
new
wire
ties
.

Tightening
Torque

"
Crankshaft
position/rpm
sensor
to
mounting
bracket
.........
.
.
5
t
1
Nm
(62
t
9
in-lb)

Crankshaft
position/rpm
sensor,



4
.
Installation
is
reverse
of
removal
.
Use
a
new
O-ring
replacing
(rear
mounted)



when
installing
sensor
.
Be
sure
wiring
is
rerouted
in
same
orientation
.
1
.
Disconnect
sensor
harness
connector
.

6502AGN56

2
.
Locatesensor
on
rear
left
sideof
cylinder
block
.
Re-
move
sensormounting
bolt
and
remove
sensorfrom
cylinder
block
.

IGNITION
SYSTEM
SERVICE

3
.
Installation
is
reverse
of
removal
.
Use
a
new
O-ring

when
installing
sensor
.
Be
sure
wiring
is
rerouted
in
same
orientation
.
Secure
sensor
using
new
wire
ties
.

NOTE-

It
may
be
easier
to
remove
the
sensor
working
from
the
underside
of
the
vehicle
.

Camshaft
Position
(CMP)
Sensor

The
camshaft
position
(CMP)
sensor
is
usedby
the
engine
management
system
for
sequential
fuel
injection
and
knock
control
.

Camshaft
position
(CMP)
sensor,

replacing
(4-cylinder
engine)

1
.
Remove
CMP
sensorfromtop
timing
cover,
just
above
coolantthermostat
housing
.
See
Fig
.
11
.

Fig
.
11
.
Camshaft
position
sensor
mounting
bolt
(arrow)
.
M42
engine
shown
.

2
.
On
M42
engines
to
9/93
:
Disconnect
CMP
harness
plug
just
above
oil
filter
housing
.

3
.
On
M42
from9/93
and
all
M44
engines
:
Remove
upper
intake
manifold
as
described
in
113
Cylinder
Head
Re-
moval
and
Installation
.
Then
unplug
CMP
sensor
har-
ness
connector
below
manifold
.

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