1994 BMW M3 catalytic converter

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

610-16



ELECTRICAL
COMPONENT
LOCATIONS

Component



Model
Year



Location



Refer
to

MixingSwitch



1992-1994



Center
console

Multi-Function
Clock



1992-1998



Center
console

Multi-information
Display
(MDI)



1992-1998



Center
console

Normal
Speed
Cooling
Fan
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

Neutral
SafetySwitch
(Automatic



1992-1998



Next
to
gear
shift
lever
in
center
console



Fig
.
29
.

Transmission
Range
Switch)

Oil
Pressure
Switch



1992-1998



Left
front
of
engine
below
intake
manifold
at
oil
filter
housing

On-Board
Computer



1992-1998



Center
console

On-BoardComputerHorn
Relay



1992-1998



Behind
glove
compartment



Fig
.
8
.
Fig
.
9
.

On-Board
Computer
Temperature



11992-1998



I
Right
front
of
engine
compartment

Sensor

Outside
Temperature
Sensor



1992-1997



Inright
front
brake
cooling
duct

Outside
Temperature
Sensor



1998



Right
rear
of
engine
compartment
behind
fresh
air
cowl

Oxygen
Sensor
HeaterRelay



1992-1998



Power
distribution
box



Fig
.
2
.

Oxygen
Sensor(s)



1992-1998



On
exhaust
pipe
ahead/behind
catalytic
converter
(M42/M44
engine)

Oxygen
Sensor
(x2)



1992-1995



On
exhaust
pipe
ahead
of
catalytic
converter
(M50/S50US
engine)

Oxygen
Sensors
(x4)



1996-1998



On
exhaust
manifold/exhaust
pípe
behind
catalytic
converter
(M52/S52US
engine)

Parking
Brake
Switch



1
1992-1998



I
On
rear
of
parking
brake
lever

Power
Distribution
Box



11992-1998



I
Rear
left
of
engine
compartment



I



Fig
.
2
.
Fig
.
7
.
Fig
.
10
.

Radio
Microswitch



1992
-
1996



Center
console
behind
radio

Radio
Receíver



1
1997-1998



1
Right
rear
luggage
compartment

Relay
And
Fuse
Box
(Power



1992-1998



I
Left
side
of
engine
compartment



I



Fig
.
2
.

Distribution
Box)



Fig
.
7
.
Fig
.
10
.

Rear
Window
Blower



1994-1998



Behind
rear
seat
(convertible)

Rear
Window
Blower
Microswitch



1994-1994



At
convertible
top
linkage

Rear
Window
Blower
Microswitch



1995-1998



Behind
rear
seat
(convertible)

Rear
Window
BlowerRelay



11994-1998



Behind
glove
compartment



Fig
.
8
.
Fig
.
9
.

Fig
.
2
.

Fig
.
30
.

Fig
.
8
.

Rear
Window
DefoggerRelay

Reversing
(Back-up)
Light
Switch

SplicePanel,
Right
Rollover
Protection
Actuator



11994-1998

COMPONENT
LOCATIONS

Table
a
.
E36
Component
Locations

1992-1998
1992-1998

1992-1998

Power
distribution
box

Right
or
left
side
top
of
transmission

Behind
glove
compartment

Behind
rear
seat
(convertible)

Fig
.
9
.

Continued

620-2
INSTRUMENTS

Fig
.1.



Instrument
cluster
retaining
screws
(arrows)
.

INSTRUMENT
CLUSTER

0012562

Fig
.
3
.



Turnbulb
base
45°
in
direction
shown
(arrow)
.

l
v



w
r
v
9



10



11



12



13



14



15



16



)7



18



19



20
y
21

1
.
Temperature
warning



12
.
Brake
fluid
warning

oo13n6



2
.
Right
turn
signal



13
.
Brake
pad
wear
warning
3
.
Instrument
lighting



14
.ABS
warning
Fig
.
2
.



Instrument
cluster
connector
locking
lever
(arrow)
.



4
.
Oil
pressure
warning



15
.
Seat
belt
warning5
.
Highbeam



16
.ASTwarning
6
.
Battery
charging
lamp



17
.Check
control
6
.
Installation
is
reverse
of
removal,
noting
the
following
:



7
.
Left
turn
signal



18
.Check
engine

"
Instrument
cluster
harness
connector
locking
levers



8
.
Low
fuel
warning



19
.
LCD
lighting

must
be
in
up
position
before
installing
connector
.



9
.
Airbag
warning



20
.
Rear
foglight
(not
used)
10
.
Catalytic
converter
warning



21
.
Front
foglights
"
Install
airbag
to
steering
wheel
as
described
in
721



11
.
Emergency
brake
Airbag
System
(SRS)
.



0012563

"
Reconnect
negative
(-)
cable
to
battery
last,
once
al¡



Fig
.
4
.



Bulb
designation
chart
.

harness
connectors
have
been
reconnected
.

"
Recode
cluster
as
described
in
Instrument
cluster,



CAUTION-
seif-testing
.



Note
wattage
of
bulb
.
Excessive
wattage
could
melt
cluster
housing
.
Replace
defective
bulbs
with

Instrument
cluster
bulbs,
replacing



reptacementbulbs
of
the
same
wattage
.

1
.
Remove
instrument
cluster
as
described
above
.



Odometer
coding
plug,
replacing

2
.
Remove
faulty
bulb
by
turning
bulb
base
45°
inits

mount
and
remove
from
housing
.
See
Fig
.
3
.



The
coding
plug
maintains
a
record
of
thevehicle
mileage
.

The
back
of
the
instrument
cluster
and
its
bulb
locations
are



1
.
Record
vehicle
mileage
.

shown
in
Fig
.
4
.
2
.
Remove
instrument
cluster
as
described
earlier
.

GRN/VIO

HOT
IN
RUNAND
START



HOT
FILM
AIR



HALLEFFECT



CRANKSHAFT



ELCTRONIC
r



-1FRONT
MASSMETER
CAMSHAFTSENSOR
POSITION/RPM
IMMOBILIZERCONTROL
I



(POWER



r
-



-
1



1



1



SENSOR



MODULE
(EWS11)
FUSE
I



FSSE



F



IDIS7RIBUTION
I
iDA
ISA
(BOX
I
I
(199fi)
(1997)
I
is
Y



iBy
$
1D01B



I



D
-
22

OXYGENSENSOR
(BEHIND
CATALYTIC
CONVERTER)
88648

FUEL
PUMP

SPLICE
BLK
-----
.--_
.-------

OXYGENSENSOR
(FRONT
OFCATALYTIC
CONVERTER)

Engine
Management

1996-971
.91-(2
of
2)

EVAPORATIVE
IDLESPEED
EMISSION
CONTROL
VALVEVALVE

ELECTRICAL
WIRING
DIAGRAMS
ELE-79

EXCEPT
1997
318
ti

INSTRUMENT
CLUSTER
SYSTEM
EXCEPT
31811

INTAKEAIR



I
CYL1-2



CYL3-4
RESONANCE



INTAKEAIR
CHANGEOVERKNOCKSENSORTEMPERATURE
VALVE



SENSOR

BLK
IENGINESPEED
I
-
2
k
I
INPUT



I
GRG=1fi~
CHECK
ENGINE
I
WHT/BLK
21
I
FUEL
X
t
fi
'C
CONSUMPTION

I
~GRN/RED
13
3
I
FUEL
I
CONSUMPTION
SRN/VI
jg
TEMPSENS
(L)
BRN/V=L
17{iTEMPSENS(-)

INSTRUMENT
CLUSTER

ENGINECOOLANT
TEMPERATURESENSOR

WW=TIBLK



BOR4
(I
I
__J
ON-BOARD
COMPUTER
BRN/RED
74,
r
_
----
I
~ITEMPSIGNAL
I
-
~GRN/RED
42
J
~IFUELCONSUMPT
I
WHT/BLK
83
~~
I
VEHICLE
SPEED
I
GRV
S,
IENGINDICATOR
I
VEL
78
-
-~{ICRNKPOS/RPM
_ILL
-(ICRNKPOSIRPM
BRN
(SHIELD
GROUND
YEL



I21



CAMSHFTPOS
GRV/BLU
17
'GROUND
GRV/V
-
10
4S
`
VEL77,
:SIGNAL

8-{
I02
SENSOR
SIG

B-
:
..
.SORGND
OISHTNGGND
VEL
19
I
B
3D~I023ENSORBIG
02SHTNGGND
BRN/VIO
B7
I
{
ACTIVATEVALVE
-
-
~BRNIG
RN29
J
I
~
I
ISC
VALVE
CTRL
BRN
2
BRNIBLU~JACTIVATE
VALVE
BIACTIVATEVALVE
-
BILK
70
'
~
BLK
40
;CVL
1-2KS
-~{
I
CYL
3-6
KS
BRN/BLK
711
SENSGROUND
BRN/RED
~
IINTKAIRTEMP
BRN/VIO
44
I



I
~
W
L~~~
THROTTLEPOS
GRVRY/
-
W
I
SVSUPPLY



I
ENGINECONTROL
MODULE
(DME)

THROTTLE
POSITION
SENSOR