diff BMW M3 1998 E36 User Guide

110-
4



ENGINE
REMOVAL
AND
INSTALLATION

Engine,
removing
and
installing

(6-cylinder
engines)

Engineremoval
procedures
for
the
various
6-cylinder
en-

gines
arecovered
in
this
section
.
Most
steps
in
theproce-

dures
are
similar
or
the
same
for
al¡
engines
.
Specific

differences
that
apply
are
noted
at
the
beginning
of
each
step
.

Be
sure
to
cover
all
painted
surfaces
before
beginning
the

removal
procedure
.
As
an
aid
to
installation,
label
all
compo-

nents,wires,
and
hoses
before
removing
them
.
Do
not
reuse

gaskets,
O-rings
or
seals
during
reassembly
.

WARNING
-

Due
to
risk
of
personal
injury,
be
sure
the
engine
is
cold
before
beginning
the
removalprocedure
.

1
.
Disconnect
negative
(-)
battery
cable
in
luggage
com-

partment
.

CAUTION-

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

2
.
Remove
engine
hood
or
place
hood
in
service
position
.

See410
Fenders,
Engine
Hood
.

NOTE-

1t
is
not
necessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.

3
.
Remove
splash
guardunder
engine,
if
applicable
.

4
.
Remove
transmission
from
car
.
See
230
Manual

Transmission
or
240Automatic
Transmission
.

5
.
Remove
vacuum
hosefrom
brake
booster
on
bulkhead
.

Cover
hole
in
booster
and
plug
hose
end
.

6
.
Remove
intake
air
plenum
panel
in
rear
of
engine
com-
partment
.
See
640
Heating
and
AirConditioning
.

7
.
Remove
ground
strap
from
timing
case
cover,
if
appli-

cable
.

8
.
Remove
top
enginecovers
and
disconnect
ignition
coil
harness
connectors
.
Working
at
fuel
injectors,
pry
open
small
wire
clipsat
each
injector
.
Remove
main
harness

hold-down
nuts
and
lift
completeharness
away
.
See
Fig
.
7
.

ENGINE
REMOVAL
AND
INSTALLATION

Fig
.
7
.



Remove
mainharnessfrom
top
engine
and
place
at
base
of

windshield
.

0012703

Fig
.
8
.



Mass
air
flow
sensor
connector
air
duct
hose
clamp,
and
air
cleaner
housing
mounting
bolts
(arrows)
.

9
.
Unbolt
andremove
complete
air
cleaner
housing
with



10
.
On
cars
with
automatic
transmission,
remove
front
and
mass
air
flow
sensor,
disconnecting
and
labeling
con-



rearbrackets
holding
transmission
cooler
linesto
side
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
8
.



of
engine
.

113-8



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

IW?
-
L
'/~f
W



~
4r

"

-
"



;,s
1

12
.
On
M44
engine
:
Place
sensor
wheel
on
intake
cam-
shaft
sprocket
so
that
arrowon
sensor
wheel
points
up
.

13
.
Instan
and
hand-tighten
sprocket
mounting
bolts
.

CAUTION-

Different
hydraulic
chaintensioners
were
used
during
manufacture,
depending
onengine
type
.
See
Fig
.
21
.
Note
that
the
late
style
tensioner
can
be
retrofitted
to
the
earlier
engine,
so
be
sure
to
identify
the
version
of
tensioner
installed
as
insta-lation
instructions
vary
between
the
two
.

14
.
On
M42
engine
:
Disassemble
chain
tensioner
by
strik-
ing
outer
sleeve
against
a
solid
object
.
This
will
release
snap
ring
and
tensioner
will
separate
.
See
Fig
.
22
.

M42
Engine

up
and
camshaft
threaded
holes
centered
in
siotted
holes
.

CYLINDER
HEAD,
4-CYLINDER

0013024a

Outer
sl
eve



Detent

ring

Spri
g

Fig
.
22
.
Disassembled
chain
tensioner
for
M42
engine
.

15
.
On
M42
engine
:
Clamp
tensioner
piston
in
vice
(soft

jaws)
.
Slowly
compress
piston,
making
sure
detent
ring

fits
into
taper
of
outer
sleeve
.
If
necessary,
press
ends

of
detent
ring
together
.
Slowly
continuepressing
ten-

sioner
together
until
snap
ring
audibly
clicksinto
outer

sleeve
.
Measure
overall
lengthof
tensioner
to
confirm

correct
assembly
:
68
.5
mm
(2.7
in
.)
.

NOTE-

i

Snap

ring

/0
.13024

The
late-style
tensioner
on
the
M44
engíne
canbe
ret-
rofitted
to
the
M42
engine
.

Tightening
Torque

"Chain
tensioner
plug
to
cylinder
head
.....
.-~
..........
40
Nm
(30
ft-Ib)

16
.
On
M44
engíne
:
Clamp
tensioner
píston
in
vice
(soft

jaws)
and
squeeze
oil
from
it
.
Slowly
compress
piston
only
up
to
end
circlip
.
Repeat
procedure
twice
to
ensure

all
oil
is
expelled
.
See
Fig
.
23
.

17
.
Instan
hydraulic
chain
tensioner
to
cylinder
head
.
Use
a
new
sealing
washer
on
tensioner
when
installing
.

18
.
On
M42
engine
:
Unlock
chain
tensioner
by
pressing
chain
rail
against
tensioner
until
it
expands
out
.

19
.
Check
that
chain
is
free
of
slack
.
Tighten
sprocket
mounting
bolts
.
Fig
.
21
.
Two
versions
of
hydraulic
chain
tensioners
.
Original
chainten-
sioner
on
M42
engine
(top)
can
be
disassembled
.
Chain
ten
sioner
on
M44
engine
(bottom)
cannotbe
disassembled
.



Tightening
Torque
Note
differences
in
outer
sleeve
.
Also,
the
M42
tensioner
de-



"
Chain
sprocket
to
camshaft
flange
.
..
10
Nm
(89
in-lb)
tent
ring
groove
(arrow)
is
visible
when
tensioner
is
extended
.

20
.
Remove
crankshaft
locking
tool
from
bellhousing
and
camshaft
locking
tool
from
rear
of
cylinder
head
.

117-
4



CAMSHAFT
TIMING
CHAIN

15
.
Remove
mounting
bolts
from
left
and
right
camshaft



4
.
Insta¡¡
and
hand-tighten
sprocket
mounting
bolts
.

sprockets
.

16
.
On
M42
engines,
remove
upper
bolt
on
right
side
chainguide
and
unbolt
lower
timing
chainguide
below
crank-
shaft
.

17
.
Remove
camshaft
sprockets
from
camshafts
together

with
chain
and
crankshaft
sprocket
.
NoteWoodruffkey
when
removing
crankshaftsprocket
.

CA
UTION-

The
crankshaft
must
not
be
allowed
to
rotate
when
the
timing
chaín
is
removed
.
The
pistons
can
contact
the
valves
.

Camshaft
timing
chain,
installing

(4-cylinder
engines)

Inspectal¡
sprockets
for
wear
or
damage
.
Inspect
the
chain
guide
and
tensioner
rails
for
grooves
caused
by
chain
contact
.

Replace
any
partthat
is
worn
.
If
any
of
the
sprockets
are
worn,
the
chain
and
sprocketsare
replaced
asan
assembly
.

The
procedure
outlined
below
assumes
that
the
camshafts
and
the
crankshaft
arelocked
in
the
TDC
installation
positionwithspecial
tools
(shown
earlier
in
Fig
.
5
and
Fig
.
6)
.

1
.
Install
timing
chain
to
crankshaft
sprocket,
then
slide
sprocket
on
crankshaft
whílealigníng
woodruff
key
.

2
.
Place
camshaft
sprockets
on
chain,
then
place
sprock-
ets
oncamshafts
so
that
arrows
on
sprockets
point
up
and
elongatedholes
in
sprockets
are
centered
lo
tapped
holes
in
camshafts
.
See
Fig
.
9
.

.
I

Pa
-
s



~_



a

Ge
..
.

0012509

5
.
On
M42
engine
:
Install
lowerchainguide
.

6
.
On
M44
engine
:
Remove
allen-head
retaining
screw
at
left
chain-guide
.
Turn
slotted-head
of
adjusting
sleeve

so
that
sleeve
contacts
cylinder
head
.
Then
install
and

tighten'allen-head
screw
fully
.
See
Fig
.
10
.

Fig
.
10
.
Left
upper
chain
guide
adjusting
sleeve
(arrow)
.
Note
cam-
shaft
position

CAUTION-

Different
hydraulic
chaintensioners
were
used
duringmanufacture,
depending
onengíne
type
.
See
Fig
.
11
.
Note
that
the
late
style
tensioner
canbe
retrofitted
to
the
earlier
engíne,
so
be
sure
to
identify
the
versíon
of
tensioner
ínstalled
as
ínstal-
lation
instructions
vary
between
the
two
.

7
.
On
M42
engine
:
Disassemble
chain
tensioner
by
strik-
ing
outer
sleeve
against
a
solid
object
.
This
will
release
snap
ring
and
tensioner
will
separate
.
See
Fig
.
12
.

8
.
On
M42
engine
:
Clamp
chain
tensioner
piston
in
vice
(soft
jaws)
.
Slowly
compress
piston,
making
sure
de-
tent
ring
fits
into
taper
of
outer
sleeve
.
If
necessary,
press
ends
of
detent
ring
together
.
Slowly
continueFig
.
9
.



Camshaft
sprockets
correctly
installed
with
arrows
pointing



pressing
tensioner
together
until
snap
ring
audibly
upand
bores
centered
to
tapped
holes
(M44
engine)
.



clicks
into
outer
sleeve
.
Measure
overall
length
of
ten-
sionerto
confirm
correct
assembly
:
68
.5
mm
(2
.7
in
.)
.

3
.
On
M44
engine
:
Place
cylinder
position
sensor
plate
on
intake
camshaft
sprocket
so
that
arrowonsensor
plate



NOTE-
points
up
.



The
¡ate-style
tensioner
on
the
M44
engine
can
be
ret-rofittedto
the
M42
engíne
.

CAMSHAFT
TIMING
CHAIN,
4-CYLINDER

M42
Engine

CL
(EM

Fig
.
11
.
Two
versionsof
hydraulic
chaintensioners
.
Original
chain
ten-
sioner
on
M42
engine
(top)
canbe
disassembled
.
Chain
ten-
sioner
on
M44
engine
(bottom)
cannot
be
disassembled
.
Note
differences
in
outer
sleeve
.
Also,
the
M42
tensioner
de-
tent
ring
groove
is
visible
when
tensioner
is
extended
(arrow)
.

Outer
sleeve
Spring

0013024a

Detent

ring

9
.
On
M44
engines
:
Clamp
tensioner
piston
in
vice
(soft

jaws)
and
squeeze
oil
from
it
.
Slowly
compress
piston

only
up
to
end
círclip
.
Repeat
procedure
twice
to
ensure

al¡oil
is
expelled
.
See
Fig
.
13
.

10
.
Insta¡¡
hydraulic
chain
tensioner
lo
cylinder
head
.
Usea
new
sealing
washer
on
tensionerplug
when
installing
.

Tightening
Torque

"
Chain
tensioner
to
cylinder
head
....
40
Nm
(30
ft-Ib)

11
.
On
M42
engines
:
Release
early-style
chain
tensioner
by
pressing
chain
guide
against
tensioner
until
it
un-

locks
and
expands
out
.

CAMSHAFT
TIMING
CHAIN



117-
5

0012507

Fig
.
13
.
When
reinstalling
chain
tensiones,
oil
in
tensioner
piston
must

first
be
expelled
by
compressing
piston
in
vise
.
When
com-
pressing
piston,
only
compress
up
to
and
circlip
(arrow)
.

Tightening
Torque

"
Chain
sprocket
lo
camshaft
flange
(M6)
..
.
..
.............
.
..
10
Nm
(89
in-lb)

13
.
Remove
crankshaft
locking
tool
from
bellhousing
and

camshaft
locking
tool
from
rear
of
cylinder
head
.

14
.
Install
lower
timingchain
cover
:

"
Insta¡¡
new
crankshaft
oil
seal
in
cover
.

"
Use
new
gaskets
when
installing
cover
.

"
Thoroughly
clean
profile
gasketgroove
and
all
gasket

sealing
surfaces
on
lowerchaincover
.

"
Apply
a
small
bead
of
silicon
sealer
(3-Bond
1209
or
Snap



equivalent)
lo
joint
corners
where
chaincover
meets

ring



0013024



head
and
block
.
See
Fig
.
14
.

"
Tap
cover
into
position
to
engage
locating
dowels
.

Fig
.
12
.
Disassembled
early-style
chain
tensioner
usadon
M42
en-



"
Tighten
cover
mounting
bolts
alternately
and
in
stages
.

gine
.

12
.
Check
that
chain
is
now
free
of
siack
.
Tighten
down

sprocket
mounting
bolts
.



where
chain
cover
meets
head
and
block
(arrows)
.
Fig
.
14
.
Apply
sealer
(3-Bond
1209
0
or
equivalent)
to
joint
corners

CAMSHAFT
TIMING
CHAIN,
4-CYLINDER

Fig
.
36
.
BMW
special
tool
no
.
11
2
300
installed
through
bellhousing
and
finto
flywheel
.

8
.
Remove
oil
line
fitting
from
VANOS
control
unit
.

NOTE-

Wrap
the
VANOS
oil
line
fitting
with
a
shop
to
absorb
leaking
oil
.

9
.
Using
hollow
bolt
and
seals
from
oil
supply
line,
instan

BMW
special
tool
no
.
11
3
450
(air
line
fitting)
and
con-
nect
a
supply
of
compressed
air
(30-115
psi)
to
VANOS

oil
fitting
.

10
.
Measure
and
record
distance
between
trigger
plate

edge
and
side
of
secondary
timing
chain
tensioner
.

See
Fig
.
37
.

Fig
.
37
.
VANOS
reference
measurement
(dimension
A)
between
trig-
ger
píate
(sender
gear)
and
side
of
secondary
chain
tensioner
.

CAMSHAFT
TIMING
CHAIN



117-
1
5

11
.
Disconnectharness
connector
from
VANOS
solenoid
.
Connect
BMW
special
tool
no
.
12
6
410
(electrical
test
lead)
to
VANOS
solenoid
connector
.

"
Connect
positive
(+)
test
lead
to
positive
(+)
terminal
ofbattery
Connect
negative
(-)
test
leadto
chassis
ground
.
solenoid
should
audibly
click
and
intake
cam-
shaft
should
advance
.

CA
UTION-

"
Be
sure
to
connect
the
test
hamess
polaritycor-
rectly
.
lf
the
polarity
is
reversed,
the
intemal
diode
in
the
VANOS
solenoid
will
be
destroyed
.
Although
the
solenoid
will
still
functionwith
a
faultydiode,
a
fault
code
may
be
set
in
the
ECM
memory
.

"
To
confirm
voltage
polarity,
turn
the
ignition
on
and
check
for
positive
(+)
batteryvoltage
at
the
terminal
corresponding
to
the
redlwhite
wire
in
the
main
harness
connector
.
Check
that
the
pos-
itive
terminal
(+)
in
the
main
connector
corre-
sponds
to
the
same
terminal
in
the
solenoid
connector
that
is
being
connected
to
the
battery
.

12
.
With
solenoid
actuated,
measure
and
record
new
dis-

tance
between
trigger
plate
edge
and
side'of
second-
ary
timing
chain
tensioner,
as
shown
in
Fig
.
37
.

13
.
Difference
between
first
measurement
(step
10)
andsecond
measurement
(step12)
should
be
at
least
8
.5
mm
(0
.3346
in
.)
.
lf
any
faults
arefound,
solenoid
may

be
faulty,
or
hydraulic
control
unit
may
be
faulty
or
incor-
rectly
installed
.

14
.
Check
VANOS
solenoid
byremoving
it
from
control
unit
.
Check
that
solenoid
plunger
and
control
unit

plunger
move
freely
.
Install
solenoid
using
tighteníng

torque
given
below
.

NOTE-

"
The
solenoid
is
available
asareplacement
part
.
lf
the
control
unit
plunger
is
sticking,
the
complete
control
unit
will
have
to
be
replaced
.

"lf
the
VANOS
system
does
not
advance
correctly
and
no
other
faults
can
be
found,
itis
possible
that
the
VANOS
control
unit
may
Nave
been
fnstalled
incor-
rectly-especially
if
the
camshaft
sprockets
have
pre-
víously
been
removed
for
other
repairs
.
Check
the
installation
by
removing
and
reinstalling
the
control
unit
as
described
later
.

VANOS
(VARIABLE
VALVE
TIMING)

119-
4



LUBRICATION
SYSTEM

15
.
Remove
oil
pan
screws
.
Lower
andremove
oil
pan
to-

ward
rear
.



Tightening
Torques

"
Control
arm
bushing
carrier

CAUTION-



to
body(M10
bolt)
...............
42
Nm
(31
ft-Ib)

'



lf
the
oil
pan
does
not
separate
easily
from
the
en-



"
Engine
mount
to

gine
cylinder
block,
make
sure
all
mounting
bolis



suspension
crossmember
(M10
nut)
.
42
Nm
(31
ft-Ib)

have
been
removed
.
If
necessary,
a
few
tapswith



"
Front
suspension
crossmember
a
rubber
mallet
shouldbreak
it
free
.
Never
pry
the



to
body
.
.
..
...
..
.
....
See
310
Front
SusPension
oil
pan
loose
.
"
Oil
pan
to
engine
block
(M6
bolt)

8
.8
grade
..
....
.
...
...
.
........
10
Nm
(89
in-lb)
16
.
Installation
is
reverse
of
removal
.



10
.9
grade
...
..
.
....
..
.
.
.
.......
12
Nm
(9
ft-Ib)

"
Thoroughly
clean
all
old
gasket
material
from
mating



"
Power
steering
pump
to
bracket

surfaces
anduse
a
new
gasket
.



(self-locking
nuts)
....
..
.
....
..
.
..
22
Nm
(16
ft-Ib)

"
Applya
small
amount
of
non-hardening
sealer
(3-



"
Power
steering
pump
bracket
to
engine

Bond
O
l209
or
equivalent)
to
oil
pan
gasket
directly



block
or
oil
pan
(self-locking
nuts)
..
.
22
Nm
(16
ft-Ib)

below
joints
for
end
cover
and
front
timing
case
cover
.



"
Stabilizer
bar
link
to
control
arm
See
Fig
.
5
.



M8
nut
.................
...
.
...
22
Nm
(17
ft-Ib)
"
When
installing
oil
pan
to
engine,
tighten
forward



M10
nut
.....................
..
42
Nm
(31
Ib-ft)
screws
first,
then
tightenrear
.



"
Steering
column
universal
joint
"
Fill
engine
with
oil
as
described
in
020
Maintenance



to
steering
rack
spindle
(M8
bolt)
....
19
Nm
(14
ft-ib)
Program
.

0011950

Fig
.
5
.



Joint-mating
areas
at
oil
pan
gasket
where
sealer
should
be
applied
(arrows)
.
Apply
a
bead
3
mm
wideby
2
mm
high
.

OIL
PAN

WARNING
-

Always
use
new
bolis
when
mounting
the
subframe
to
the
body
.
The
one-timeonly
bolis
shouldbe
re-
placed
any
timethey
are
removed
.

NOTE-

The
oil
pickup
is
attached
to
the
oil
pan
using
self-tap-
ping
screws
.
For
this
reasonno
threading
for
the
pickup
is
present
on
new
oil
pans
.
Replace
the
seal
for
the
pickup
and
use
the
oíd
screws
to
rea
ttach
the
pickup
to
the
pan
.

Oil
pan,
removing
and
installing

(6-cylinder
engine,
1992models)

NOTE-

Cars
built
up
to
9/92
(1992models)usea
different
sus-
pension
crossmember
than
later
production
cars
.
Oil
pan
removalprocedureon
the
earlier
cars
requires
that
the
engine
be
raised
and
supportedfrom
above
.

1
.
Raise
car
and
place
securely
on
jackstands
.

2
.
Remove
splash
shield(s)
from
under
engine,
where
ap-

plicable
.

3
.
Drain
engine
oil
as
described
in
020
Maintenance
Pro-

gram
.

4
.
Remove
complete
exhaust
system
.
See180
Exhaust

System
.

5
.
Remove
air
filter
housing
complete
with
mass
air
flow

sensor
.
See
113
Cylinder
Head
Removal
and
Instal-

lation
.

6
.
Remove
alternator
cooling
duct
from
alternator
and
ra-
diator
support
.

7
.
Remove
radiator
cooling
fan
and
fan
shroud
.
Remove

radiator
securing
clips
at
top
of
radiator
.
See
170
Radi-

ator
and
Cooling
System
.

Center
the
steering
spindle
to
the
steering
rack
before
in-



NOTE-

stalling
the
steering
column
shaft
.
See
320
Steering
and



The
radiator
cooling
fan
nut(32
mm
wrench)
has
left

Wheel
Alignment
for
specific
installation
markings
and
pro-



hand
threads
.

cedures
.

119-
6



LUBRICATION
SYSTEM

17
.
Raise
engine
as
much
as
possible
.
Check
carefully
for



22
.
Installation
is
reverse
of
removal
.

obstructions,
wiring
harness
clearance
and
pinched

hoses
or
lines
as
engine
is
raised
.



"
When
installing
oil
pan,
apply
a
b



d
of
non-hardening

sealing
compound
(3-Bond
1209
0
or
equivalent)
to

18
.
Remove
oil
pan
mounting
bolts
and
lower
oil
pan
to



front
and
rear
end
cover
seam
areas
on
block
.

subframe
crossmember
.



"
Position
oil
pump
pickup
tube
and
oil
pan
onto
block

and
install
pickup
tube
using
a
new
gasket
.

"
Be
sure
tab
on
gasket
faces
down
towards
intake
of

NOTE-



pickup
tube
.
If
the
oil
pan
does
not
separate
easily
from
the
engine



"
Tightenforward
oil
pan
screws
first,
then
tighten
rear
.

cylinder
block,
afew
taps
with
arubber
mallet
should



"
Fill
engine
with
oil
as
described
in
020
Maintenance
break
it
free
.
Do
not
pry
the
oil
pan
loose
.



Program
.

"
After
adding
engine
oil,
start
and
run
engine
.
Raise
en-

19
.
Remove
oil
pump
sprocket
mounting
nut
.
See
Fig
.
9
.



gine
speed
to
2,500
rpm
until
oil
pressure
warning

Lift
sprocket
off
together
with
drive
chain
.



lampgoes
out(about
5seconds)
.

Fig
.
9
.
Oil
pump
sprocket
mounting
nut
(left-hand
thread)
on
6-cylin-



OII
pan,
removing
and
installing

derengine(arrow)
.



(6-cylinder
engine,
1993
and
later
modeis)

NOTE-

The
oíl
pump
sprocket
nut
has
left
hand
threads
.

20
.
Unbolt
oil
pump
pickup
tubefrom
oil
pump
.
Unbolt
oil

pump
from
engine
block
.
See
Oil
pump,
removing

and
installing
(6-cylinder
engine)
.

21
.
Remove
oil
pan
from
rear
.

Tightening
Torques

"
Engine
mount
to

suspension
crossmember(M10
nut)
..
42
Nm
(31
ft-Ib)

"
Oil
pan
to
engine
block
(M6
bolt)

8
.8
grade
....
..
.
...
...
.
........
10
Nm
(89
in-lb)

10
.9
grade
.
.
..
.
..
...
.
.
.
.
.
.....
12
Nm
(106
in-lb)

"
Oil
pump
to
engine
block
.
...
...
.
..
22
Nm
(16
ft-Ib)

"
Oil
pump
sprocket
to
oil
pump
shaft

(M1
0x1
left-hand
thread)
...
..
.
.
..
.
25
Nm
(18
ft-Ib)

"
Power
steering
pump
to
bracket

(self-locking
nuts)
.....
.
....
..
.
...
22
Nm
(16
ft-lb)

"
Power
steering
pump
bracket
to
engine

block
or
oil
pan
(self-locking
nuts)
.
..
22
Nm
(16
ft-Ib)

NOTE-

Cars
built
after
9/92
use
a
different
suspension
cross-

member
¡han
earfier
productíon
cars
.
Oil
pan
removal

procedure
on
the
later
cars
requíres
that
the
engine
be

supported
from
aboye
and
the
front
suspension
cross-

member
be
unbolted
and
loweredfrom
the
chassis
.

1
.
Raisecar
and
place
securely
on
jackstands
.

2
.
Remove
splash
shield
fromunder
engine,
if
applicable
.

3
.
Drain
engine
oil
as
descríbed
in
020
Maintenance
Pro-

gram
.

4
.
Remove
alternator
cooling
duct
from
alternator
and
ra-

diator
support
.

119-
1
0



LUBRICATION
SYSTEM

Oil
pump,
removing
and
installing

(6-cylinder
engine)

Oil
pressure
on
the
6-cylinder
engines
is
generated
by
a
gear-type
pump
bolted
to
the
bottom
of
the
engine
block
.
The
oil
pump
is
chain
driven
off
the
front
of
the
crankshaft
.

NOTE-

Oil
pump
removal
requires
raising
the
engine
(cars
built
up
to
9-92)
or
lowering
the
front
suspension
crossmem-
ber
(cars
built
from
9-92)
to
remove
the
oil
pan
.

1.
Drain
oil
as
described
in
020
Maintenance
Program
.

2
.
Remove
oil
pan
as
described
earlier
.

3
.
Remove
oil
pump
sprocket
mounting
nut
(left-hand
thread)
.
See
Fig
.
16
.
Lift
sprocket
off
together
with
drive
chain
.

Fig
.
16
.
Oil
pump
sprocket
mounting
nut
(left-hand
thread)
on
6-cylin-
der
engine
(arrow)
.

4
.
Remove
mounting
bolts
from
oil
pump
and
oil
pump
pickup
tube
.
Withdraw
pump
.

NOTE-

Note
any
spacers
between
pump
and
engine
block
.
See
Fig
.
17
.

"
Note
position
of
locating
dowels
.

OIL
PUMP

811186

0011952

Fig
.
17
.
Oil
pump
mounting
points
(1)
and
pickup
tube
mountíng
points
(2)
.

5
.
Remove
coverfrom
oil
pump
and
check
for
wear
or
scoring
.
Spin
oil
pump
shaft
and
check
that
gears
turn
smoothly
.
Replace
pump
if
gears
spinwith
difficulty
or
any
wear
is
present
.

6
.
Installation
is
reverse
of
removal,
noting
the
following
:

"
Align
sprocket
splines
to
oil
pump
shaft
splines
before

tightening
sprocket
nut
.

Tightening
Torques

"
Oil
pump
to
engine
block
(M8)
......
22
Nm
(16
ft-Ib)

"
Oil
pan
to
engine
block
(M6
bolt)

8
.8
grade
..
...
.
...
...
.
.........
10
Nm
(89
in-lb)

10
.9
grade
.
...
.
..
....
.
........
12
Nm
(106
in-lb)

"
Oil
pump
sprocket
to
oil
pump
shaft
(M1
0x1
left-hand
thread)
..........
25
Nm
(18
ft-Ib)

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

130-2



FUEL
INJECTION

GENERAL

This
repair
group
covers
fuel
injection
system
component

testing
and
repair
.
Special
equipment
is
necessary
for
some

of
the
procedures
given
in
this
repair
group
.
If
you
do
not
have

the
equipment
required
to
do
the
job,
it
is
recommended
that

these
repairs
be
left
to
an
authorized
BMW
dealer
.
The
BMW

dealer
is
equipped
with
sophisticated
diagnostic
test
equip-

ment
that
is
capable
of
quicklypinpointing
hard-to-find
fuel
in-

jection
problems
.

NOTE-

"
Wiring
diagrams
for
the
engine
management
system,

can
be
found
at
the
rear
of
the
manual
under
Electri-
cal
Wiring
Diagrams
.

"
For
ignition
system
repairinformation,
see120
Igni-

tion
System
.

"
For
fuel
supply
system
testing
and
repair,
see160



The
engine
control
module
(ECM)
uses
electrical
signals

Fuel
Tank
and
Fuel
Pump
.



from
the
mass
air
flow
sensor,
the
air
and
coolant
temperature

sensors,
the
crankshaft
position/rpm
sensor,
the
knock
sen

Principies
Of
Operation



sors
and
the
oxygen
sensorsas
the
primary
inputs
to
electron-

ically
control
fuel
delivery
and
ignition
timing
.

There
are
five
versions
of
engine
management
systems

usedon
the
E36
cars
.
Each
has
the
same
basic
components

and
operating
principles
.
The
most
notable
difference
is
that

1996
and
later
cars
use
a
sophisticated
OBD
II-compliant
sys-

tem
.
See
Table
a
.

Table
a
.
Engine
Management
System
Variants

Engine
code/year



1
System

4-cy1inder
M42
(1
.8
I)
1992-1995



Bosch
DME
Ml
.7
M44
(1
.91)
1996-1998



~
Bosch
DME
M5
.2
(OBD
II)

6-cylinder
M50
1992
(2.5
I)



Bosch
DME
M3
.1
1993-1995
(2.5
I)



Bosch
DME
M3
.3.1
(VANOS)
M52
1996-1998
(3281-
2
.8
I)



Siemens
MS
41
.1
(OBD
II)
1998
(3231
-
2
.5
I)



Siemens
MS
41
.1
(OBD
II)
M-Power
S50US
(M3
-
3
.01)
1995



Bosch
DME
M3
.3
.1
S52US
(M3
-
3
.21)
1997-1998



Siemens
MS
41
.1
(0131)
11)

NOTE-

-
Descriptions
and
procedures
in
the
first
partof
this
re-

pairgroup
refer
to
all
the
various
engine
management
systems
.

"
Particulars
of
each
fuel
injection
system
are
treated
in
separate
sections
in
the
second
part
of
this
repair
group
.

GENERAL

Fig
.1
.



OBD
II
diagnostic
connector
locatíon
.

The
fuel
injection
system
is
completely
electronic
in
opera-

tion
.
Air
flow
is
measured
electronically
via
a
mass
air
flow

sensor
and
additional
sensors
supply
information
about
en-

gine
operating
conditions
.
The
ECM
calculates
the
amount
of
fuel
needed
for
the
correct
air-fuel
ratio
and
actuates
the
fuel

injectors
accordingly
.
The
amount
offuel
metered
to
theen-

gine
is
determined
by
how
long
the
injectors
are
open
.

Airintake
.
Air
entering
the
engine
passes
through
a
pleat-

ed
paper
air
filter
in
the
air
cleaner
.
Intake
air
volume
or
mass

is
then
measured
bya
mass
air
flow
(MAF)
sensor
.
In
al¡
ex-

cept
the
vane
type
sensor
(DME
M1
.7),
a
reference
current
is

used
to
heat
a
thin
wireor
film
in
the
sensor
when
the
engine

is
running
.
The
current
used
to
heat
the
wire/film
is
electroni-

cally
converted
into
a
voltage
measurement
corresponding
to

the
mass
of
the
intake
air
.

Table
b
.
Mass
Air
Flow
Sensor
Variants

System



Al
r
flow
sensor
type

Bosch
DME
M1
.7



Vane
(volume
sensor)

Bosch
DME
M3
.1



Hot
wire
(mass
sensor)

Bosch
DME
M3
.3
.1



Hot
film
(mass
sensor)

Bosch
DME
M5
.2



Hot
film
(mass
sensor)

Siemens
MS
41
.1



Hot
film
(mass
sensor)

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



NOTE-

the
lower
left
dashpanel
.
See
Fig
.
1
.



On
cars
equipped
wíth
tractioncontrol,
an
additional
throttle
valve
is
controlled
by
an
electronic
throttle
actu-
ator
(motor)
.
This
valve
is
used
for
engine
speed
inter
vention
.
Repair
information
forthis
system
is
notcovered
here
due
to
the
special
electrical
testing
equip-
ment
required
to
service
it
.