1993 BMW M3 throttle
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020
Maintenance
Program
GENERAL
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020-2
BMW
Service
Indicator
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020-2
Oil
Service
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020-2
Inspection
I
and
Inspection
II
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020-2
Resetting
Service
Indicator
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020-3
MAINTENANCE
TABLES
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020-3
FLUID
AND
LUBRICANT
SPECIFICATIONS
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020-8
Manual
Transmission
Fluid
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020-8
Automatic
Transmission
Fluid
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020-8
Final
Drive
Gear
Oil
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020-9
Brake
Fluid
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020-9
Engine
Coolant
(Anti-freeze)
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020-9
Power
Steering
Fluid
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020-9
ENGINE
OIL
SERVICE
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020-9
Engine
oil,
checking
leve¡
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020-9
Engine
oil
and
filter,
changing
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020-9
ENGINE
COMPARTMENT
MAINTENANCE
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020-10
Air
filter,
replacing
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020-11
Spark
plugs,
replacing
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020-11
¡dle
Speed
.
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020-12
Battery,
checking
and
cleaning
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020-12
Battery,
replacing
.
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020-12
Accelerator
and
Throttle
Linkage
.
.....
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020-13
Engine
DriveBelts
.....
.
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...
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020-13
V-belt,
replacing
(4-cylinder
engines
built
up
to
1/94)
..
....
.
020-13
Poly-ribbed
belt,
replacing
(4-cylinder
engines
built
from
1194
and
all
6-cylinder
engines)
.
.
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020-13
Cooling
System
Service
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020-14
Power
steering
fluid,
checking
leve¡
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020-14
Oxygen
Sensors
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020-15
MAINTENANCE
PROGRAM
020-1
UNDER-CAR
MAINTENANCE
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.020-16
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Fuel
filter,
replacing
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.020-16
Tires,
checking
inflation
pressure
.
.....
.
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020-17
Tires,
rotating
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020-17
Wheels,
aligning
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.
...........
.
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'020-17
Brake
system,
inspecting
.
.
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020-17
Brake
pad/rotor
wear,checking
.
......
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020-17
Brake
fluid,
replacing
.........
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020-17
Parking
brake,
checking
......
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020-17
Exhaust
system,
inspecting
....
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.020-18
Manual
Transmission
Senrice
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020-18
Manual
transmission
fluida
checking
and
filling
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020-18
AutomaticTransmission
Service
.
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020-18
Front
suspension
and
steeringlinkages,
inspecting
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.020-18
Rear
suspension,
inspecting
.
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020-18
Final
drive
oil
leve¡,
checking
.
.
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020-18
Fuel
tank
and
fuel
lines,
inspecting
.
.....
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020-19
Clutch
fluid,
checking
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020-19
Drive
axle
joint
boots,
inspecting
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020-19
BODY
AND
INTERIOR
MAINTENANCE
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.020-19
Windshield
Wiper
Blade
Maintenance
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020-19
Body
and
hinges,
lubricating
.
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020-19
Seat
Belts
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020-20
Exterior
Washing
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.020-20
Waxing
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020-20
Polishing
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.'020-20
Washing
Chassis
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020-20
Special
Cleaning
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.020-20
Interior
Care
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020-20
Leather
Upholstery
and
Trim
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020-20
TABLES
a
.
Oil
Service
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020-4
b
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Inspection
1
Service
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020-5
c
.
Inspection
11
Service
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020-6
d
.
Scheduled
Maintenance-Time/Mileage
Intervals
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020-7
e
.
Fluids
and
Lubricants
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020-8
Page 28 of 759
020-6
MAINTENANCE
PROGRAM
Group
310/330
Table
c
.
Inspection
II
Service
a
d
d
a
a>
0
d
a
r
.c
mm
L
m
y
L
E
ó
3
E
ó
Maintenance
ítem
l
o-
z
~
c
Engine
compartment
maintenance
Inspect
V-belt
/Poly-ribbeddrive
condition
.
Check
V-belt
tension,
if
applicable
.
Lubricate
throttle
linkage
.
Replace
air
filter
.
Change
oil
and
oil
filter
.
Replacespark
plugs
.
Repair
Group
120
Check
brake/clutch
fluid
leve¡
.
Check
battery
acid
leve¡
and
correct
asnecessary
.
Repair
Group
121
Check
engine
coolant
leve¡
and
anti-freeze
protection
and
add
asnecessary
.
Inspect
for
cooling
system
leaks
.
Repair
Group
170
Under
car
maintenance
Change
automatic
transmission
fluid
.
Repair
Group
240
Change
manual
transmission
oil
.
Repair
Group
230
Check
clutch
plate
for
wear
.
Repair
Group
210
Check
drive
axle
boots
for
leaks
.
Repair
Group
330
Change
final
drive
fluid
(1995
and
later
models
:
change
synthetic
oil
every
2nd
Inspection
II)
.
Replace
fuel
filter
.
Check
fuel
tank,
fuel
lines,
and
af
connections
for
leaks
.
Inspect
exhaust
system
.
Repair
Group
180
Check
steering
gear
and
steering
¡inkages
.
Check
power
steering
system
for
leaks
.
Check
fluidleve¡
.
Repair
Group
320
Inspect
brake
system
for
damaged
hoses
and
lines,
leaks
or
damage
.
Remove
calipers
and
check
brake
pad
wear
.
Check
brake
rotors
for
scoring
damage
.
Repair
Group
340
Check
parking
brake
operation,
adjust
cable
if
necessary
.
Check
thickness
of
parking
brake
lin-
ings
.
Repair
Group
340
Inspect
front
and
rear
suspension,
including
front
and
rear
wheel
bearings,
for
play
.
Repair
Inspect
wheels
and
tires,
including
spare,
check
tire
pressure
and
condition
.
Body
and
Interior
Maintenance
Lubricate
door
hinges
and
hood
latch,
hood
hinges
.
Check
headlight
and
driving
light
aiming
and
adjust
asnecessary
.
Check
operation
of
headlights,
parking
lights,
back-up
lights,
licenseplate
lights,
interior
lights,
glove
box
light,
engine
compartment
light,
trunk
light,
instrument
panel
lights,
turn
signals,
emer-gency
flashers,
stop
lights,
horns,
headlight
flasher
anddimmer
switch
.
Check
active
check
control
panel
forfauits
(where
applicable)
.
6
Electrical
System
MAINTENANCE
TABLES
Continued
on
next
page
Page 35 of 759
Accelerator
and
Throttle
Linkage
The
accelerator
and
throttie
linkage
should
be
lubricated
pe-
riodically
.
Use
a
general
purpose
oil
on
the
joints
and
bearings
of
the
linkage
.
Use
a
multipurpose
grease
on
the
bearing
points
of
the
throttie
plate
.
Engine
Drive
Belts
Drive
belts
and
pulleys
transfer
power
from
theengine
crank-
shaft
to
various
accessories
.
See
Fig
.
13
.
Depending
on
model
and
model
year,
engine
driven
accessories
are
driven
by
V-
belts,
poly-ribbed
(serpentine)
belts,
or
a
combination
of
the
two
.
For
example,
early
4-cylinder
engines,
usetwo
V-belts
and
one
poly-ribbed
belt
.
Inspect
drivebelts
with
the
engine
off
.
lf
the
belt
shows
signs
of
wear,
cracking,
glazing,
or
missing
sections,
it
should
be
re-
placed
immediately
.
V
belt,
replacing
(4-cylinder
engines
built
up
to
1194)
0012472
Fig
.
13
.
Drive
belt
and
tensioner
assembly
for
late
4-cylinder
engine
wíth
poly-ribbed
drive
belt
.
V-belts
should
be
inspected
during
regular
maintenance
in-
tervais
.
Incorrect
tension
can
decrease
the
life
of
the
belt
and
the
component
it
drives
.
The
V-belt
tension
is
adjusted
through
a
toothed-rack
mechanism
.
Inspect
belts
with
the
engine
off
.
Twist
the
beltto
inspect
its
sidewalls
and
bottom
.
Beltstructural
damage,
glazed
or
shiny
sidewaljs
caused
by
a
loose
belt,
orseparation
are
al¡
reasons
to
replace
a
belt
.
Replacement
of
the
V-belts
every
four
years
is
recommend-
ed
.
Loosen
the
mounting
bolts
and
adjust
the
belt-driven
unit
until
the
belt
tension
is
as
loose
aspossible
.
Remove
the
belt
by
slipping
it
over
the
pulleys
.
In
some
cases
it
may
be
necessary
to
removeone
V-belt
to
get
to
another
.
Use
a
torque
wrench
and
a
crowfoot
wrench
to
turn
the
tensioning
gear
bolt
and
set
belt
tension
.
Hold
the
wrench
steady
and
tighten
the
locknut
on
the
rear
of
the
tensioning
gear
bolt
.
Tighten
al¡
other
mounting
nuts
.
MAINTENANCE
PROGRAM
020-
1
3
NOTE-
"
For
the
most
accurate
check,
V-belt
tension
should
be
checked
using
a
V-belt
tension
gauge
.
"
Belt
squealing
is
normally
caused
by
loose
beltten-sion
.
Belt
dressings
should
not
be
used
.
Tightening
Torques
"
Tensioning
gear
(alternator
belt
tensioning)
.
.
.
...............
7
Nm
(62
in-lb)
"
Tensioning
gear(power
steering
belt
tensioning)
...
..
...
8
to
8
.5
Nm
(71
to
75
in-lb)
"
Tensioning
gear
locking
nut
.......
24
Nm
(18
ft-Ib)
NOTE-
When
belts
are
replaced
with
new
ones,
store
the
old
set
in
the
luggage
compartment
for
emergency
use
.
When
installing
a
new
belt,
gently
pry
it
over
the
pulleys
.
Too
much
force
may
damage
the
belt
or
the
accessory
.
Tension
the
belt(s),
runthe
engine
for
a
few
minutes
(at
least
1500
rpm),
then
recheck
the
belt
tension
.
CAUTION-
Do
not
over
tighten
the
V-belts
.
Overtightening
will
cause
shaft
bearings
to
fail
prematurely
.
Poly-ribbed
belt,
replacing
(4-cylinder
engines
buiit
from
1194
and
all
6-cylinder
engines)
An
automatic
belt
tensioner
is
used
to
keep
the
belts
ten-
sioned
properly
.
Unless
the
tensioner
mechanism
malfunc-
tions,
the
poly-ribbed
belts
do
not
require
tension
adjustment
.
To
reduce
the
chance
ofbelt
failure
while
driving,
replace-
ment
of
the
belts
every
four
years
is
recommended
.
Mark
drive
belt
rotationdirectíon
if
removing
and
reusing
an
old
belt
.
To
remove
the
belt,
it
is
necessary
toretract
the
self-tension-
er
.
Using
a
breaker
bar
or
other
long
socket
assembly,
rotate
the
tensioner
to
loosenthe
belt
.
See
Fig
.
14
or
Fig
.
15
.
On
4-cyl-
inder
engines,
it
will
benecessary
to
remove
the
A/C
compres-
sor
belt
to
remove
the
main
drive
belt
.
WARNING
-
Observe
care
when
replacing
the
belt
.
Personal
in-
jury
could
result
if
the
tensioner
springs
back
into
position
uncontrollably
.
With
the
belt
removed
from
the
pulleys,
inspect
the
pulleys
for
wear
or
damage
that
may
cause
early
failureof
the
new
belt
.
This
is
also
a
good
opportunity
to
inspect
the
belt-driven
acces-
sories,
checking
for
bearing
wear
and
excess
play
.
Drive
belt
routing
is
shown
in
Fig
.
16
and
Fig
.
17
.
ENGINE
COMPARTMENT
MAINTENANCE
Page 45 of 759
camshaft
secondary
drive,
causing
thecamshaft
to
"advance"
12
.5°
.
The
helical
gears
are
cut
so
that
forward
motion
of
the
gear
cup
is
transiated
into
rotational
motion
of
the
camshaft
.
See
117
Camshaft
Timing
Chain
for
testing
and
repair
infor-
mation
on
the
VANOS
system
.
DISA
(Dual
Resonance
Intake
System)
DISA,usedon
4-cylinder
engines,
is
a
dual
intake
runner
system
that
effectively
provides
the
advantages
of
both
short
and
long
intake
runners
within
the
same
engine
.
For
best
per-
formance,
long
intake
runners
aremost
beneficial
atlow-
and
mid-engine
speeds
(below
4,200
rpm),
and
short
intake
run-
ners
enhance
torque
at
high
engine
speeds
(above4,200
rpm)
.
NOTE-
The
term
DISA
comes
from
the
German
words
Differ-
enzierte
Sauganlage,
and
can
roughty
be
transiated
as
a
differing
intake
manifold
configuration
.
The
DISA
solenoid
valve
is
controlled
by
the
DME
control
module,
using
engine
speed
as
the
primary
input
.
The
main
components
of
the
system
are
the
modified
twin-section
in-
takemanifoldwith
change-over
valve,
the
twin-barrel
throttle
body,
and
the
electrical/pneumatic
actuating
components
.
See
Fig
.
4
.
r
I
I
I
?
,
in
UpPer,
take
-1
manifold
1
-1
Throttle
housing
(Heated)
q
:lZU
Fig
.
4
.
DISA
system
components
.
DISA
changes
the
intake
runner
length
based
on
engine
speed
.
The
DISA
system
electro-pneumatically
changes
the
intake
runner
length
through
the
twin-section
intake
manifold
and
a
change-over
butterfly
valve
.
The
change-over
valve
is
located
at
a
point
in
the
intake
manifold
where
four
pipes
come
into
two
.
When
the
change-over
valve
is
closed,
the
4-way
primary
intake
manifold
and
the
2-way
ram
air
manifold
areconnected
to
make
the
"long"
configuration
.
When
the
change-overvalve
opens,
intake
air
flow
is
redirected
through
only
the
short
4-
way
primary
intake
manifold
.
The
change-over
valve
is
held
in
the
normally
open
position
bya
spring
.
Thisallows
for
an
open
valve
in
the
event
of
sys-
tem
failure
.
During
low
andmid
enginespeeds,
the
DME
con-
trol
module
supplies
power
to
the
solenoid
valve,
which
in
turn
allows
vacuum
to
be
applied
lo
the
vacuum
diaphragm
.
This
causes
the
valve
to
close
(long-pipe
configuration)
.
When
en-
gine
speed
reaches
approximately
4,800
rpm,
the
DME
con-
trol
module
electrically
signals
the
solenoid
valve
and
the
valve
opens,
creating
the
short
pipe
configuration
:
Further
detafs
on
DISA
canbefound
in
130
Fuel
Injection
.
Engine
Management
System
Al¡
enginescoveredby
this
manual
usean
advanced
engine
management
system
called
Digital
Motor
Electronics
(DME)
.
In
the
DME
system,
advancedOn-Board
Diagnostics
(OBD),
fuel
injection,
ignition,
and
otherfunctions,
are
combined
under
the
control
of
theEngine
Control
Module
(ECM)
.
See
Fig
.
5
.
-
Lower
intake
manifold
DISAvacuum
'
~servo
EíY1z
ENGINE-GENERAL
100-
3
le
-
DISA
solenoid
valve
0012591
/
with
butterfly
va¡
GENERAL
Page 46 of 759
100-4
ENGINE-GENERAL
'
TEMP
PRECAT
POST
CAT
OXYGENSENSOR
HEATING
#
.
THROTTLE
POSITION
FUEL
INJECTOR
CONTROL
(SEQUENTIAL)
OPERATING
POWER
00
CAMSHAFT
POSITION
SENSOR
ECM
I
MAIN
GROUND
RELAY
J_
-
AC
COMPRESSOR
RELAY
CONTROL
TERMINAL
15
MEMORY
POWER
FUEL
PUMP
RELAY
CONTROL
AUX
GROUND
P
CRANKSHAFT
POSITION
dESENSOR
INTAKE
AIR
ENGINE
COOLANT
TEMP
FUEL
TANK
PRESSURE
SENSOR
S-EML
S-MSR
ASC
S-ASC
VEHICLE
SPEED
LOW
FUEL
LEVEL
A/C
SWITCH
ON
(AC)
E36
IHKA
COMPRESSOR"ON"
SIGNAL
(KO)
INDIVIDUAL
SERIAL
NUMBER
MS41
.1
SECONDARY
AIR
1NJECTION
AIR
PUMP®
RELAY
CONTROL
IDLE
CONTROL
VALVE
'M
FUEL
INJECTION
(TI)
ENGINE
SPEED
(TD)
Fig
.
5
.
Siemens
MS
41
.1
OBD
II
engine
management
systemusedon
1996
and
later
M52
engines
.
GENERAL
IGNITION
COILS
CONTROL
L
r"Q
if~
CIYVFIYC
CHE
AMP
CONTROL
ENGINE
THROTTLE
POSITION
6
ECM
RELAY
CONTROL
ASC
THROTTLE
..
:
.
.
..
-11
1Q\\\
POTENTIOMETER
POWER
CAN
TCM
II
SCAN
(DES
;
ER
DIAGNOSIS
OBD
II
I
II
GENERIC
SCANTOOL
0012596
Page 51 of 759
NOTE-
"
On
carswith
OBD
ti,
specialized
OBD
11
scan
tool
equipment
must
be
used
to
access
the
DTCs,
either
using
the
BMW
special
tool
ora
`generic"
OBD
11
scan
tool
.
See
130
Fuel
Injection
.
"
The
08D
11
fault
memory
(including
an
iiluminated
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
.
Table
d
.
OBD
1
Fault
(Blink)
Codes
(1992-1995
modeis
only)
Graphic
representation
of
flashing
Check
Engine
light
fault
code
:
1221
5
Seconds
.
:-
2
.5~-
--05--
Fault
code
and
meaning
1
Corrective
action
Code
1216
:
Throttle
potentiometer
Code
1218
:
Output
stage,
group#1
(DME
3
.3
.ionly)
Code
1219
:
Output
stage,
group
#2
(DME
3
.3.1
only)
Code
1221
:
Oxygen
sensor
#1
Code
1224
:
Air
temperature
sensor
(NTC)
Code
1226
:
Knock
sensor
#2
(DME
3
.3
.1
only)
130
ENGINE-GENERAL
100-
9
2
.5
seconds,
then
go
off
for
2
.5
seconds
.
At
thispoint,
the
fault
codes
will
begin
to
flash
.
See
Table
d
.
If
more
than
one
fault
has
been
detected,
eachcode
will
be
separated
by
a2
.5
second
pause
.
When
al¡
fault
codes
havebeen
displayed,
there
will
be0
.5
second
flash
and
thenthe
light
will
remain
off
.
To
read
the
codes
again,
turn
the
key
off
and
then
on
again
.
Depress
theaccelerator
pedal
to
the
floor
five
times
quickly
(within
5
seconds)
.
The
codes
will
begin
to
repeat
.
On
cars
with
OBD
I,
fault
codes
can
be
read
by
turning
the
To
erase
the
fault
code
memory,
first
make
sure
the
fault
ignition
key
on
and
fully
depressing
theaccelerator
pedal
to
code
1000
(short
blink
and
then
light
goes
out
for
long
period)
the
floor
five
times
within
five
seconds
.
TheCheck
Engine
is
present,
then
depress
the
throttle
fully
for
at
least
10
sec-
light
will
then
remain
on
for
five
seconds,
blink
off,
come
on
for
onds
.
Read
the
fault
codes
as
described
earlier
and
check
for
the
1444
code
(no
faults
stored)
.
-,--------------
Check
Engine
light
on
Check
Engine
light
off
Code
1211
:
DM
E
Control
Module
DME
control
module
may
be
faulty
.
This
code
appears
if
the
control
module
fails
the
self
test
.
Check
inputsto
control
module
.
Repair
Group
130
Code
1215
:
Mass
air
flow
sensor
Check
air
flow
or
mass
air
flow
sensor
and
wiring
to
sensor
.
Repair
Group
130
Test
throttle
potentiometer
resistance
and
wiring
.
Repair
Group
130
Test
DME
control
module
input/outputs
.
Repair
Group
130
Test
DME
control
module
input/outputs
.
Repair
Group
130
Check
sensor
output
signal
to
DME
control
module
.
Repair
Group
Code
1222
:
Oxygen
sensor
lean/rich
control
stop
Check
for
intake
air
leaks
or
reasons
forrich
míxture
.
See
Driveabil-
ity
Troubleshooting
given
earlier
in
this
repair
group
Code
1223
:
Coolant
temperaturesensor
(NTC)
1
Test
coolant
temperature
sensor
.
Repair
Group
130
Test
intake
air
temperature
sensor
.
Repair
Group
130
Code
1225
:
Knock
sensor#1
(DME
3
.3
.1
only)
1
Check
knocksensorand
sensor
wiring
.
Repair
Group
120
Check
knocksensor
and
sensor
wiring
.
Repair
Group
120
Code
1231
:
Batteryvoltage
monitor
Test
battery
voltage
and
battery
check
charging
system
and
starter
.
Repair
Group
121
Code
1234
:
Speedometer
"A"signal
(DME
3
.3
.1
only)
Check
wiring
between
instrument
cluster
and
DME
control
module
.
Electrical
Wiring
Diagrams
Code
1237
:
A/C
compressor
cutoff
(DME
3
.3
.1
only)
Test
DME
control
module
inputs/outputs
from
A/C
system
.
Repair
Group
130
Code
1242
:
A/C
compressor
signal
(DME
3
.3.1
only)
Test
DME
control
module
inputs/outputs
from
A/C
system
.
Repair
Group
130
DRIVEABILITY
TROLIBLESHOOTING
Page 54 of 759
100-
1
2
ENGINE-GENERAL
NOTE-
The
oxygen
sensor
signal
is
ignored
until
the
engine
reachesa
specified
minimum
temperature
.
Therefore,
The
primary
input
usedby
the
fuel
injection
system
to
deter-
when
troubleshooting
cold
engine
driveability
prob-
mine
how
much
fuel
should
be
delivered
is
the
signal
from
the
lems,
the
oxygensensor
canbe
ruled
out
asa
possible
mass
air
flow
sensor
in
the
intake
air
ductwork
.
cause
.
As
the
oxygen
sensor
ages,
its
ability
to
react
quickly
to
changing
conditions
deteriorates,
and
it
may
eventually
cease
to
produce
any
signal
at
all
.
To
check
the
operation
of
the
oxy-
gen
sensor,
see
130
Fuel
Injection
:
NOTE-
On
1996
and
latercars,
OBD
11
enhanced
emission
standards
require
the
engine
control
module
(ECM)
to
monitor
the
oxygen
content
in
the
exhaust
both
before
and
after
the
catalytic
converter
.
Thisallows
for
tighter
control
of
the
tail
pipe
emissions
and
also
allowsthe
ECM
to
diagnose
converter
problems
.
If
the
DME
de-
tects
that
catalytic
converter
or
oxygensensor
efficien-
cyhas
degraded
pasta
certain
pre-programmed
limit,
it
will
turn
on
the
Check
Engine
light,
and
store
a
diag-
nostic
trouble
code
(DTC)
in
the
ECM
.
DRIVEABILITY
TROUBLESHOOTING
Catalytic
B9506
Air
Flow
Measurement
and
Vacuum
Leaks
Because
proper
fuel
metering
depends
on
accurate
mea-
surement
of
the
incoming
air,
any
unmeasured
air
that
enters
the
engine
downstream
of
the
mass
air
flow
sensor
will
cause
a
lean
air-fuel
mixture
and
possibly
affectdriveability
.
NOTE-
Fig
.
10
.
Regulating
oxygen
sensor
measures
oxygen
content
of
ex-
gattery
Voltage
hausY
gas
as
indicator
of
.¡_fi
.1
ratio
and
"-k,
.
E-
effi-
ciency
.
Monitoríng
oxygen
sensor
(not
shown)
monitors
If
a
large
air
leak
is
causing
driveability
problems,
the
Check
Engine
light
will
usually
be
illuminated
and
a
fault
will
be
stored
in
the
fault
code
memory
.
See
On
Board
Diagnostics
(OBD)
.
There
are
many
places
for
unmeasured
air
to
enter
theen-
gine
.
First,
inspect
all
hoses,
fittings,
ducts,
seals,
and
gaskets
in
the
intake
air
tract
for
cracks
or
looseness
.
It
may
be
neces-
sary
to
remove
parts
that
cannot
be
fully
checked
in
their
in-
stalled
positions
.
Also
make
sure
all
of
the
intake
manifold
and
throttle
body
mounting
nuts
are
tight
.
In
addition
to
air
leaks,
air
restrictions
can
also
cause
drive-
ability
problems
.
Remove
the
air
filter
and
hold
it
up
to
a
strong
light
source
.
If
the
filter
does
not
pass
light,
it
is
restricted
and
should
be
replaced
.
Also,
remove
the
intake
air
ductwork
and
check
for
oily
deposits
at
the
throttle
plate
.
Buildup
in
this
area
can
cause
an
erratic
idle
.
Clean
away
any
deposits
using
a
cloth
wetted
withcarburetor
cleaner
and
reinstall
the
ductwork
.
CAUTION-
Do
not
spray
carburetor
cleaner
directly
in
the
throt-
tle
anea
.
Spraying
cleaner
may
force
it
into
the
throt-
tle
position
switch
or
sensor
and
cause
damage
.
catalytic
converter
operation
.
All
of
the
electrical
components
in
the
fuelinjection
and
igni-
tion
systems
require
a
minimum
voltage
to
operate
properly
.
When
troubleshooting
engine
driveability
problems,
one
of
Replacement
of
oxygensensors
at
the
specified
intenrals
en-
the
first
checks
should
be
to
make
sure
the
battery
is
fully
sures
that
the
engine
and
emission
control
system
wili
continue
charged
and
capable
of
delivering
allits
power
to
the
electricalto
operate
as
designed
.
As
the
oxygen
sensor
ages,
its
ability
to
system
.
react
quickly
to
changing
conditions
deteriorates,
and
it
may
eventually
cease
to
produceany
signal
at
all
.
To
make
a
quick
check
of
battery
charge,
measure
the
volt-
age
across
the
battery
terminals
with
all
cables
attached
and
As
the
oxygen
sensor
ages,
its
ability
to
react
quickly
to
the
ignition
off
.
A
fully
charged
battery
will
measure
12
.6
volts
changing
conditions
deteriorates,
and
it
may
eventually
cease
or
slightly
more,
compared
to
12
.15
volts
for
a
battery
with
a
to
produce
any
signal
at
all
.
To
check
theoperation
of
the
oxy-
25%
charge
.
gen
sensor,
see130
Fuel
Injection
.
Even
a
fully
charged
battery
cannot
deliver
power
unless
it
is
properly
connected
to
the
electrical
system
.
Check
the
bat-
tery
terminals
for
corrosion
and
loosecableconnections
.
If
the
battery
does
not
maintain
the
proper
voltage,
the
charging
system
may
be
atfault
.
See
121
Battery,
Starter,
Alternator
.
Page 57 of 759
al
Icld
Table
e
.
Engine
Driveability
Troubleshooting
c
l
1
I
f
I
I
Oxygen
sensor
faulty
Test
oxygen
sensor
.
ENGINE-GENERAL
100-
1
5
SYMPTOMS
a
.
Engine
fafs
tostart
b
.
Engine
startsbut
stops
immediately
c
.
Erratic
engine
idle
d
.
Poor
engine
responseon
acceleration
e
.
Erratic
engine
operation
in
al¡
speed
ranges
f
.
Excessive
fuel
consumption
g
.
Poor
enginepower,
fails
to
rev
up
h
.
CO
content
toolow
i.
CO
content
too
high
CAUSES
CORRECTIVE
ACTION
a
Fuel
pump
faulty
Test
fuel
pump
.
Repair
Group
160
a
e
Ignition
system
faulty
Test
ignition
system
.
Repair
Group
120
a
Main
relay
or
fuel
pump
relay
faulty
Test
main
relay
.
Repair
Group
130
a
Crankshaft/rpm
position
sensor
faulty
Test
crankshaft/rpm
sensor
.
120
b
c
h
i
ldle
speed
control
valve
faulty
Test
idle
speed
control
valve
.
c
d
e
Throttle
position
sensor
faulty
or
idle
signal
to
Test
throttle
position
sensor
.
DME
control
module
missing
.
c
d
h
i
Mass
air
flow
sensor
faulty
Test
mass
air
flow
sensor
Repair
Group
130
a
b
c
d
e
h
Large
air
intake
system
leak
Check
for
major
intake
air
leaks
downstream
of
mass
air
flow
sensor
.
a
c
d
e
g
h
Fuel
pressure
too
low
Test
fuel
pressure
.
Repair
Group
130
?
I
F
ue
l
pr
essu
r
e
t
oo
high
T
est
f
u
el
pressure
.
Repair
Group
130
d
e
g
h
Fuel
pump
delivery
volume
too
low
Test
fuel
pump
delivery
volume
.
Repair
Group
160
a
c
e
f
h
q
C
oo
l
a
nt
t
e
mp
e
r
a
t
u
r
e
se
n
so
r
f
au
lty
--]
T
est
coo
l
a
n
t
temp
erature
sensor
.
c
e
~
f
i
~
Fuel
injectors
leaking
Check
fuel
injectors
and
replace
leaking
injectors
.
~
Repair
Group
130
Throttle
plate
binding
or
incorrectly
adjusted
Check
throttle
plate
and
adjust
if
necessary
.
a
c
Electrical
connections
loose,
broken,
or
cor-
Visually
inspect
connectors
and
correct
any
roded
faults
.
Repair
Group
600
Ground
connections
loose,
broken,
or
corroded
Visually
inspect
ground
connections
and
correct
any
faults
.
Repair
Group
600
c
e
~
f
CO
content
too
high
Test
air
flowor
mass
air
flow
sensor
.
Repair
~
Group
130
a
b
c
d
e
CO
content
too
low
Test
mass
air
flow
sensor
.
gb
c
d
e
f
g
h
i
Inputsignals
to
ECM
missing,
ECM
in
limp
Make
electrical
tests
at
DMEECM
relay
.
Repair
home
mode
Group
130
a
~
b
~
c
~
d
e]
f
g
h
i
ECM
faulty
Test
DMEECM
inputs
.
If
all
inputs
are
correct,
replace
ECM
.
DRIVEABILITY
TROUBLESHOOTING