oxygen sensor BMW 328i 1997 E36 Owner's Manual
Page 176 of 759
130-
3
0
FUEL
INJECTION
Pin
Signal
Component/function
Signal
ECM
PIN
ASSIGNMENTS
Table
1.
ECM
Pin
Assignment-Bosch
DME
M3
.1
1
output
Fuel
pump
relay
control
Fuel
pump
relay
switches
with
engine
runningor
cranking
(crankshaft
position
Signal
mustbe
present
for
relay
switchover)
2
1
output
1
Idle
speed
control
valve
1
Pulsad
ground-
close
signal
(seealsopin29)
3
output
Fuel
injectorcontrol,
cyl
.
1
Pulsedground
(injection
pulsewidth
in
ms)
with
engine
running
4
output
Fuel
injectorcontrol,
cyl
.
3
Pulsedground
(injection
pulsewidth
in
ms)
with
engine
running
5
output
Fuel
injector
control,
cyl
.
2
Pulsedground
(injection
pulse
width
in
ms)
with
enginerunning
6
ground
Ground
Ground
for
fuel
injector
output
stages
7
vacant
-
-
8
output
Check
Engine
Check
éngine
lamp
control
ground
9
vacant
-
-
10
vacant
-
-
11
output
Throttle
valve
position
Load
signal
to
transmission
control
module
12
input
Throttle
position
sensor
Voltage
varies
with
throttle
position
13
output
Mass
air
flow
sensor
Air
flow
sensor
hotwire
burn
off
(voltage
for
0
.5
seconds
after
shutdown)
14
ground
Mass
air
flow
sensor
Ground
for
air
flow
sensor
15
vacant
-
-
16
input
Cylinder
identification
sensor
A/C
voltage
pulse
per
camshaft
revolution
(between
pin
16
and
44)
17
output
Fuel
consumption
(ti)
Fuel
consumption
output
(KVA
Signal)
to
instrument
cluster
18
vacant
-
-
19
vacant
-
-
20
vacant
-
-
21vacant
-
-
22
vacant
-
-
23
output
Ignition
control
(terminal
1),
cyl
.
no
.
2
Primary
Signal,
ignition
coil
cyl
.
no
.
2
24
output
Ignition
control
(terminal
1),
cyl
.
n
o
.
3
Primary
signal,
ignition
coil
cyl
.
no
.
3
25
output
Ignition
control
(terminal
1),
cyl
.
n
o
.
1
Primary
signal,
ignitioh
coil
cyl
.
no
.
1
26
input
Power
supply
(terminal
30)
Battery
voltage
(B+)
at
al¡
times
(terminal
30)
27
output
Main
relay
control
Main
relay
activation
(to
relay
terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-
open
signal
(see
also
pin
2)
30
vacant
-
-
31
output
Fuel
injector,cyl
.
no
.
5
Pulsedground
(injection
pulsewidth
in
ms),
cyl
.
no
.
5
32
output
Fuel
injector,cyl
.
no
.
6
Pulsedground
(injection
pulse
width
in
ms),
cyl
.
no
.
6
33
output
Fuel
injector,cyl
.
no
.
4
Pulsedground
(injection
pulsewidth
in
ms),
cyl
.
no
.
4
34
ground
Ground
Ground
for
output
stages
35
vacant
36
output
Evaporative
purgevalve
control
Pulsed
ground
with
engine
at
normal
temperature
and
varying
engine
load
37
output
Oxygen
sensor
heater
relay
control
Oxygen
sensor
heater
relayactivation
(ground
at
terminal
85)
38
vacant
-
-
39
vacant
-
-
40
vacant
-
41
input
Mass
air
flow
sensor
Voltage
(+)
42
vacant
-
-
43
ground
Ground
Ground
for
temperatura
sensors
(ECT
sensor,
IAT
sensor,
TP
sensor)
44
input
Cylinder
identification
sensor
A/C
voltagepulseper
camshaft
revolution
(between
pin
16
and
44)
Page 177 of 759
Table
i
.
ECM
Pin
Assignment-Bosch
DME
M3
.1
Pin
Signal
Component/function
2
ignal
FUEL
INJECTION
130-
3
1
45
vacant
-
46
vacant
-
-
47
vacant
-
-
48
output
A/C
compressor
control
A/C
compressor
disabled
via
compressor
control
relay
49
vacant
-
-
50
output
Ignition
control
(terminal
1),cyl
.
n
o
.
4
Primary
signal,
ignition
coil
cyl
.
n
o
.
4
51
output
Ignition
control
(terminal
1),cyl
.
n
o
.
6
Primary
signal,
ignition
coil
cyl
.
no
.
6
52
output
Ignition
control
(terminal
1),cyl
.
n
o
.
5
Primary
signal,
ignitioncoil
cyl
.
no
.
5
53
vacant
-
54
input
Power
supply
Battery
voltage
(+)
from
main
relay
terminal
87
55
ground
Ground
Ground
for
ignition
control
56
input
Power
supply
(terminal
15)
Batteryvoltage
(+)
with
key
on
or
engine
running
57
vacant
-
-
58
vacant
-
-
59
output
Throttleposition
sensor
Throttleposition
sensorsupply
voltage
(5
VDC)
60
input
Data
link
connector
Programming
voltage
61
vacant
-
-
62
vacant
-
-
63
vacant
-
-
64
input
Ignition
timing
intervention
from
A/T
control
module
(only
active
during
gearshift)
65
input
Automatic
transmission
(A/T)
range
switch
Transmission
park
or
neutral
signal
66
vacant
-
-
67
input
Engine
speed/crankshaft
position
sensor
Crankshaft
position/rpm
(voltage
(VAC)
between
pins
67
and
68)
68
input
Engine
speed/crankshaft
position
sensor
Crankshaft
position/rpm
(voltage
(VAC)
between
pins
67
and
68)
69
vacant
-
-
70
input
Oxygen
sensor
Oxygen
sensor
signal
(0-1
VDC
fluctuating
with
engine
running)
71
ground
Oxygen
sensor
Oxygen
sensor
signal
ground
72
vacant
-
-
73
input
Road
speed
Road
speed
signal
from
instrument
cluster
74
output
Engine
speed
(TD)
Engine
speed
(TD)
signalto
instrument
cluster
75
vacant
-
-
76
vacant
-
-
77
input
Intakeair
temperature
(IAT)
sensor
Intake
air
temperature
(0-5
V,
temperaturedependent)
78
input
Engine
coolant
temperature
(ECT)
sensor
Engine
coolant
temperature
(0-5V,
temperature
dependent)
79
vacant
-
-
80
vacant
-
-
81
input
On-boardcomputer
Drive-away
protection
enable
82
vacant
-
-
83
vacant
-
-
84
vacant
-
-
85
input
A/C
pressure
switch
From
Integrated
climate
control
module
via
A/C
pressure
switch
86
input
A/C
compressor
on
From
Integrated
climate
control
module
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)signal
to
pin
15
in
Data
link
connector
88
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
20
in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 178 of 759
130-
3
2
FUEL
INJECTION
Pin
1
Signal
1
Component/function
1
Signal
1
output
Fuel
pump
relay
control
Fuel
pump
relay
switches
with
engine
running
or
cranking
(crankshaft
position
signal
must
be
present
for
relay
switchover)
2
output
Idle
speed
control
valve
Pulsed
ground-close
signal
(seealso
pin
29)
3
output
Fuel
ínjectorcontrol,
cyl
.
5
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
5
4
output
Fuel
injectorcontrol,
cyl
.
6
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
6
5
output
Fuel
injectorcontrol,
cyl
.
4
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
4
6
ground
Ground
Ground
for
fuel
injector
output
stage
7
output
Camshaft
actuator
(VANOS
solenoid)
control
Camshaft
actuator
(VANOS
solenoid)
8
output
Check
Engine
Instrument
cluster,
Check
Engine
lamp
9
vacant
-
-
10
vacant
-
-
11
output
Throttle
position
Throttle
angle
signal
to
A/T
control
module
12
vacant
-
-
13
input
Oxygen
sensor
Oxygen
sensor
signal
(0-1
VDC
fluctuating
with
engine
running)
14
input
Mass
air
flow
sensor
Mass
air
flow
sensor
15
ground
Ground
Ground
16
input
Crankshaft
position/rpm
sensor
Voltage
pulse
(VAC)
between
pin
16
and
43
(crank
position/rpm
sensor)
17
input
Camshaft
position
sensor
Halleffect
camshaft
sensor
18
vacant
-
-
19
vacant
-
-
20
vacant
-
-
21
vacant
-
-
22
vacant
-
-
23
output
Ignition
coil
control,
cyl
.
4
Ignition
coil
4
24
output
Ignition
coil
control,
cyl
.
6
Ignition
coil
6
25
output
Ignition
coil
control,
cyl
.
5
Ignition
coil
5
26
input
Power
supply
(terminal
30)
Battery
voltage(B+)
at
all
times
27
input
Main
relay
control
Main
relayactivation
(terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(seealsopin
2)
30
vacant
-
-
31
output
Fuel
injectorcontrol,
cyl
.
3
Injection
pulse
wicith
in
ms-cyl
.
3
32
output
Fuel
injectorcontrol,
cyl
.
2
Injection
pulse
wicith
in
ms-cyl
.
2
33
output
Fuel
injectorcontrol,
cyl
.
1
Injection
pulsewidth
in
ms-cyl
.
1
34
ground
Ground
Ground
for
remaining
output
stages
35
vacant
-
-
36
output
Evaporative
purge
valve
control
37
vacant
-
-
38
output
Oxygen
sensor
heater
relay
control
Oxygen
sensor
heater
relay
switchover
(terminal
85)
39
vacant
-
-
40
ground
Oxygen
sensor
Oxygen
sensor
signal
ground
41
input
Mass
air
flow
sensor
Mass
air
flow
voltage
signal
42
input
Vehicle
speed
Vehicle
speed
signal
from
instrument
cluster
43
input
Crankshaft
position/rpm
sensor
Voltage
pulse
(VAC)
between
pin16
and
43
44
ground
Ground
Ground
for
intake
air
temp
.
sensor,
engine
coolant
temp
.
sensor,
throttle
position
sensor
ECM
PIN
ASSIGNMENTS
Table
j
.
ECM
Pin
Assignment-Bosch
DME
M3
.3
.1
Page 180 of 759
130-
34
FUEL
INJECTION
Pin
i
Signal
1
Component/function
1
Signal
1
output
Oxygen
sensor
(monitoring
sensor)heater
Oxygen
sensor
heater
control
(switched
ground)
2
output
Idle
speed
control
valve
Pulsed
ground-close
signal
(see
also
pin
29)
3
output
Fuel
injector
control,
cyl
.
1
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
1
4
output
Fuel
injector
control,
cyl
.
4
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
4
5
not
used
-
-
6
ground
Ground
Ground
for
fuel
injector
output
stage
7
not
used
-
8
1
output
1
Check
Engine
1
Instrument
cluster,
Check
Engine
lamp
9
not
used
-
-
10
input
Electronic
immobilizer
control
(EWS
II)
Electronic
immobilizer
control
(EWS
II)
module
11
output
Automatic
climate
control
Automatic
climate
control,
to
evaporator
controlier
12
not
used
-
-
13
not
used
-
-
14
not
used
-
-
15
not
used
-
-
16
input
Intake
air
temperature
Intake
air
temperature
Signal
17
input
Mass
air
flow
meter
Intake
air
signal
18
not
used
-
-
19
input
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
control
20
output
Crankshaft/rpm
sensor
Crankshaft/rpm
sensor
control
21
input
Camshaft
position
sensor
Camshaft
position
signal
22
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignitioncoil
3
23
output
Ignition
coil
control,
cyl
.
4
Primary
signal,
ignitioncoil
4
24
not
used
-
-
25
not
used
-
-
26
input
Power
supply
(terminal
30)
Battery
voltage
(B+)
at
al¡
times
27
input
Main
relay
control
Main
relay
activation
(terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(seealsopin
2)
30
output
Oxygen
sensor
(monitoring
sensor)
heater
Oxygen
sensor
heater
control
(switched
ground)
31
output
Fuel
injectorcontrol,
cyl
.
3
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
3
32
output
Fuel
injector
control,
cyl
.
2
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
2
33
I
not
used
40
input
Knock
sensor
#2
(cyl
.
3,4)
Knock
sensor
#2
signal
41
not
used
-
-
42
input
Vehicle
speed
Vehicle
speed
signal
from
instrument
cluster
43
not
used
-
-
44
output
Throttleposition
sensor
(TPS)
Throttleposition
reference
signal
ECM
PIN
ASSIGNMENTS
Table
k
.
ECM
Pin
Assignment-Bosch
DME
M5
.2
34
ground
Ground
Ground
for
ECM/
output
stages
35
not
used
-
-
36
input
A/C
compressor
relay
A/C
compressor
relay
control
37
not
used
-
-
38
not
used
-
-
39
not
used
-
-
Page 181 of 759
Table
k
.
ECM
Pin
Assignment-Bosch
DME
M5
.2
(continued)
Pin
I
Signal
1
Componentltunction
1
Signal
45
I
output
I
Mass
air
flow
meter
I
Intake
airSignal
46
output
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
control
47
not
used
-
48
not
used
-
49
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coil
1
50
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
51
not
used
-
52
not
used
-
53
input
Throttleposition
sensor
Throttleposition
Signal
54
input
Power
supply
Batteryvoltage
from
main
relay
(terminal
87)
55
ground
Ground
Ground
for
ECM
56
input
Power
supply
(terminal
15)
Battery
voltage
with
key
on
or
engine
running
57
output
Activate
cooling
fan
(man
.
trans
.)
control
Normal
speed
relay
58
not
used
-
-
59
not
used
-
-
60
input
Programming
voltage
Programming
voltage
via
data
link
connector,
pin
18
61
output
Evaporative
emissionvalve
Evaporative
emission
valve
control
62
vacant
-
-
63
output
Fuel
pump
relay
Fuel
pump
relay
control
64
not
used
-
65
not
used
-
-
66
not
used
-
-
67
not
used
-
-
68
input
Signal
above
80°C(man
.
tran
.)
Double
temperature
switch
69
input
Automatic
climate
control
Automatíc
climate
control
70
input
Knock
sensor
#1
(cyl
.
1,2)
Knock
sensor
#1
Signal
71
ground
Ground
Ground
for
analog
signals
and
knock
sensors
72
not
used
-
-
73
not
used
-
-
74
input
Engine
coolant
temperature
sensor
Engine
coolant
temperatura
Signal
75
not
used
-
-
76
not
used
-
-
77
output
Oxygen
sensor
(regulating
sensor)
Oxygen
sensor
control
78
input
Crankshaft/rpm
sensor
Crankshaft
position/rpmSignal
79
input
ABS
or
traction
control
ABS
or
AST
control
80
input
Engine
speed
Engine
speed
Signal
81
not
used
-
-
82
not
used
-
-
FUEL
INJECTION
130-
3
5
83
input
On-board
computar
From
On-boardcomputer
(terminal
4)
84
not
used
-
-
85
not
used
-
-
86
not
used
-
-
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)signal
to
pin
15
in
Data
link
connector
88
output
I
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
17in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 182 of 759
130-
3
6
FUEL
INJECTION
Pin
1
Signal
1
Componentffunction
1
Signal
1
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
2
output
Ignition
coil
control,
cyl
.
4
Primary
signal,
ignitioncoil
4
3
output
Ignition
coil
control,
cyl
.
6
Primary
signal,
ignition
coil
6
4
ground
Ground
Ground
5
output
Fuel
injectorcontrol,
cyl
.
2
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
2
6
output
Fuel
injectorcontrol,
cyl
.
1
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
1
7
output
Mass
air
flow
meter
Mass
air
meter
signal
8
input
Mass
air
flow
meter
Mass
air
meter
signal
9
output
Instrument
cluster
Fuel
consumption
signal
10
output
Engine
coolant
temperature
(ECT)
sensor
ECT
signal
11
output
Fueltankpressure
sensor
Fueltankpressure
sensor
control
12
input
Throttleposition
sensor
(TPS)
Throttleposition
signal
13
-
14
input
Intake
air
temperature
(IAT)
sensor
Intake
air
temperature
signal
15
Traction
control
AST
module
16
input
Automatic
climate
control
Automatic
climate
control
17
18
input
Electronic
immobilizer
control
(EWS
II)
Electronic
immobilizer
control
(EWS
II)
module
19
Automatic
climate
control
Automatic
climate
control
20
-
Instrument
cluster
Instrument
cluster
21
output
Camshaft
actuator
(VANOS
solenoid)
control
Camshaft
actuator
(VANOS
solenoid),
switched
ground
22
output
Fuel
injectorcontrol,
cyl
.
3
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
3
23
Fuel
injectorcontrol,
cyl
.
6
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
6
24
Fuel
injectorcontrol,
cyl
.
4
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
4
25
output
Oxygen
sensor
heater
control
Oxygen
sensor
heater
ground
26
input
Power
supply
(terminal
30)
Battery
voltage(B+)
at
all
times
27
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(see
also
pin
53)
28
ground
Ground
Ground
29
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coíl
1
30
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignition
coil
3
31
output
Ignition
coil
control,
cyl
.
5
Primary
signal,
ignition
coil
5
32
ground
Ground
Ground
33
output
Fuel
injector
control,
cyl
.
5
Pulsedground
(injection
pulsewidth
in
ms)
cyl
.
5
34
ground
Ground
Ground
35
output
Secondary
air
injection
Secondary
air
injection
pump
relay
control
36
output
Engine
speed
output
Engine
speed
signal
37
-
38
ground
Knock
sensor
Shielding
for
knock
sensors
39
output
Intake
air
temperature
sensor
(IAT
Sensor)
Voltagesupply
to
IAT
sensor
and
ECT
sensorEngine
coolant
temperature
(ECT)
sensor
40
output
Crankshaft
position
sensor
(Hall
effect)
Crankshaft
position
sensor
control
41
ground
Camshaft
position
(CMP)
sensor
Shielding
for
CMP
sensor
42
output
Throttle
position
sensor
(TPS)
TPS
ground
43
input
Camshaft
position/rpm
sensor
Camshaft
position/rpm
sensor
control
44
output
Throttle
position
sensor
(TPS)
Voltagesupply
to
TPS
(5
VDC)
45
Traction
control
AST
module
46
-
Instrument
cluster
Instrument
cluster
ECM
PIN
ASSIGNMENTS
Table
I.
ECM
Pin
Assignment-Siemens
DME
MS
41
.1
Page 183 of 759
Table
I
.
ECM
Pin
Assignment-Siemens
DME
MS
41
.1
(continued)
Pin
I
Signal
I
Component/function
1
Signal
FUEL
INJECTION
130-
37
47
-
48
input
Crankshaft
position
sensor
(Hall
effect)
Crankshaft
position
sensor
control
49
input
Power
supply
(terminal
15)
Batteryvoltage
with
key
onor
engine
running
50
output
Solenoid
valve
(running
losses)
Running
losses
51
output
Carbon
canister
valve
Carbon
canister
valve
control
52vacant
-
53
output
Idle
speed
control
valve
Pulsed
ground-close
signal
(seealsopin29)
54
input
Power
supply
Battery
voltagefrom
main
relay
(terminal
87)
55
vacant
-
56
-
57
input
Knock
sensor
(cyl
.
1-3)
Knock
sensor
input
Signal
58
output
Knock
sensor
(cyl
.
1-3)
Knock
sensor
control
59
input
Knock
sensor
(cyl
.
4-6)
Knock
sensor
input
Signal
60
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
18
in
Data
link
connector
61
output
Oxygen
sensor
heater
(monitoring
sensor)
Oxygen
sensor
heater
ground
62
output
Secondary
air
injection
Secondary
air
injection
control
valve
63
output
Knock
sensor
(cyl
.
4-6)
Knock
sensor
control
64
input
Camshaft
position/rpm
sensor
Camshaft
position/rpm
sensor
control
65
input
Camshaft
position/rpm
sensor
Camshaft
position/rpm
sensor
control
66
-
67
output
Oxygen
sensor
Oxygen
sensor
reference
voltage
68
output
Evaporative
purge
valve
control
Pulsed
ground
with
engine
at
normal
temperature
and
varyingengine
load
69
output
Fuel
pump
relay
control
Fuel
pump
relay
switches
with
engine
runningorcranking
(crankshaft
position
signal
must
be
present
for
relay
switchover)
70
vacant
-
-
71
output
Oxygen
sensor
heater
(regulating
sensor)
Oxygen
sensor
heater
ground
72
output
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
referencevoltage
73
input
Main
relay
control
Main
relay
activation
(terminal
85)
74
output
A/C
compressor
control
A/C
compressor
relay
control
75
input
Oxygen
sensor
Oxygen
sensor
signal
76
not
used
-
-
77
input
Oxygen
sensor
(regulating
sensor)
Oxygen
sensor
signal
78
input
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
signal
79
output
Oxygen
sensor
(regulating
sensor)
Oxygen
sensor
referencevoltage
80
Traction
control
AST
module
81
Traction
control
AST
module
82
Traction
control
AST
module
83
output
Crankshaft
position
sensor
(Hall
effect)
Crankshaft
position
sensor
control
84
vacant
-
-
85
output
Automatic
transmission
Automatic
transmission
control
module
86
input
Automatic
transmission
Automatic
transmissíon
control
module
87
input
Power
supply
Battery
voltage
from
main
relay
(terminal
87)
88
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
17
in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 207 of 759
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
Page 208 of 759
180-2
EXHAUST
SYSTEM
a
EXHAUST
SYSTEM
REPLACEMENT
Fig
.
2
.
Exhaust
systemon
1992-1995
6-cylinder
engines
.
3251
(M50)
exhaust
system
shown
.
E~
)l-,malo
m~=
i
32592-95
1
.
Front
pipe
with
catalytic
convertor
6
.
Bracket
11
.
Bracket/clamp
(2)
16
.
Rear
pipewith
muffler
2
.
Gasket
(2)
7
.
Bracket
(2)
12
.
Rubber
mounting
ring
(2)
17
.
Rubber
mount
3
.
Exhaust
manifold
8
.
Bracket
13
.
Flange
18
.
Support4
.
Exhaust
manifold
9
.
Bracket
14
.
Gasket
(48mm)
19
.
Bracket
5
.
Manifold
gasket
10
.
Oxygen
sensor
15
.
Gasket
(48mm)
eme°"
k
:I>
-
8a
1
.
Exhaust
manifold
7
.
Front
pipe
with
catalytic
con-
9
.
Bolt
(M8X90)
14
.
Brackets
(rear
muffier)
2
.
Nut
(M10)
vertor
10
.
Compression
spring
15
.
Rear
muffler
and
pipe
3
.
Gasket
(clty
.
2)
8
.
Oxygen
sensor
(regulating)
11
.
Self-lockingnut
(M8
16
.
Bracket
(transmission)
4
.
Gasket
-tightento
55
Nm
(41
ft-Ib)
-always
replace
17
.
Brackets
(transmission)
5
.
Nut
8a
.
Oxygen
sensor
(monitoring)
12
.
Bracket
(rear
pipe)
6
.
Bolt
(M8X55)
-tightento
55
Nm
(41
ft-Ib)
13
.
Rubber
mounting
ring
(9ty
2)
Fig
.
3
.
Exhaust
systemon
1996-1998
4-cylinder
(M44)
engine
.1992-1995
4-cylinder
engine
exhaust
system
is
similar
.
Page 209 of 759
1
.
Gaskets
5
.
Front
pipe
with
catalytic
con-
8
.
Flange
2
.
Exhaust
manifold
verter
9
.
Bolt
(M8x55)
3
.
Exhaust
manifold
6
.
Oxygen
sensor
(monitoring)
10
.
Rubber
mounting
ring
(48mm)
4
.
Oxygen
sensor
(regulating)
7
.
Nut
(M8)
11
.
Rear
pipewith
mufflers
Fig
.
4
.
Exhaust
systemon
1996-1998
6-cylinder
engines
.
M3
(S50US)
exhaust
system
shown
.
Exhaust
system,
removing
and
installing
NOTE-
The
automatic
transmission
will
be
supported
by
the
This
section
covers
removing
the
exhaust
system
as
a
com-
rear
crossmember
once
the
brace
is
removed
.
plete
unit
.
Once
the
system
is
removed
from
the
car,
individual
pipes
and
mufflers
can
be
more
easily
replaced
.
1.
With
exhaust
system
fully
cold,raise
and
support
car
for
access
to
exhaustsystem
.
WARNING
-
Do
not
work
undera
lifted
car
unless
it
is
solidly
supported
on
jack
stands
designed
for
that
pur-
pose
.
Never
work
under
a
car
that
is
supported
solely
by
a
jack
.
2
.
Disconnect
oxygen
sensor
connector(s)
.
NOTE
-
On
1996
and
later
cars
with
multiple
oxygen
sensors,
label
the
oxygen
sensor
connectorsbefore
disconnect-
ing
.
4
.
Where
applicable,
remove
support
brace
from
trans-
mission
.
See
Fig
.
5
.
EXHAUSTSYSTEM
180-
3
3
.
Loosen
andremove
bolts
holding
front
exhaust
pipes
to
exhaust
manifolds
.
transmission
.
See
Fig
.
6
.
0011940
Fig
.
5
.
Crossbracemounting
bolts
(arrows)
.
5
.
Disconnect
exhaust
support
bracket
assembly
from
6
.
Supportexhaustsystem
from
below
and
dísconnect
rubbersupports/rubber
rings
from
exhaust
system
.
Re-
move
exhaust
system
from
below
.
See
Fig
.
7
.
EXHAUST
SYSTEM
REPLACEMENT