d
a
d
_
L
G>
G1
a
N
.
G1
Ñ
N
N
O
.
r
d
Maintenance
ítem
°
~
Z
~
i
I
D
i
Body
and
Interior
Maintenance
(cont
.)
Replace
ventilation/A/C
micro-filter
.
Check
function
of
air
conditioning
.
Repair
Group
640
Check
function
of
seat
belts
.
Repair
Group
720
Check
windshield
washer
fluid
level
and
concentration,
add
asnecessary
.
Check
operation
of
washer
system
.
Check
condition
of
wiperblades
Repair
Group
611
Tighten
nuts
and
belts
for
door
locks
and
striker
plates
.
Replace
batteries
for
alarm/remote
control
in
masterkey
(where
applicable)
.
Check
ground
connection
(mounting
screws)
of
SRS
(airbag)
front
sensor
to
body,
if
applicable
.
Repair
Group
721
Road
Test
Check
braking
performance,
steering,
HVAC,
manual
or
automatic
transmission,
and
mirrors
Service
Interval
Reset
Reset
service
indicator
using
specialreset
tool
.
Maintenance
ítem
Replace
oxygen
sensor
.
Repair
Group
180
1992-1994
1995-
on
Flush
and
replace
brake
fluid/clutch
fluid
.
Repair
Group
340
Drain
and
flush
cooling
system
and
replace
coolant
.
Repair
Group
170
1992-19961997-1998
Anti-corrosion
warranty
inspection
.
Tablec
.
Inspection
II
Service
(continued)
Cabled
.
Scheduled
Maintenance-Time/Mileage
Intervais
MAINTENANCE
PROGRAM
020-7
e
~
e
e
i
:
l=
N
l
"
NM
I
«)
al
aN
-
11
>
O
Ó
I
Ó
I`
Ó
d
Ny
.
0
°
_
VÑ
Ñ
Ñ
1
ZG
NN
MAÍNTENANCE
TABLES
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
020-
1
8
MAINTENANCE
PROGRAM
Fig
.
25
.
Inspect
brake
pads
with
the
caliper
removed
.
Minimum
brake
pad
thickness
shown
by
dimension
(A)
.
NOTE-
The
parking
brake
may
lose
some
of
its
effectiveness
if
it
is
not
used
frequently
.
This
is
due
to
corrosion
build-
up
on
the
parking
brake
drum
.
To
remove
corrosion,
ap-
plythe
parking
brake
just
until
it
begins
togrip,
then
pulí
the
lever
up
one
more
stop
(click)
.
Drive
thecar
approx-
imately
400
meters
(1,300
ft
.)
and
release
the
brake
.
To
recheck
the
adjustment
of
the
parking
brake
see340
Brakes
.
UNDER-CAR
MAINTENANCE
0011920
Manual
transmission
fluid,
checking
and
filling
The
manual
transmission
fluid
leve¡
should
be
checked
at
specified
intervals
.
Check
and
fill
the
transmission
with
the
car
ona
leve¡
surface
.
Transmission
(luid
leve¡
checking
and
re-
placement
procedures
are
covered
in
230
Manual
Transmis-
sion
.
Automatic
Transmission
Service
The
automatic
transmission
is
not
equipped
with
a
dipstíck
.
Therefore,
checking
the
ATF
level
is
an
ínvolved
procedure,
which
includes
measuring
and
maintaining
a
specified
ATF
temperature
during
the
checking
procedure
.
For
more
complete
ATF
service,
including
checking
ATF
lev-
e¡
and
ATF
filter
replacement
procedures,
see
240
Automatic
Transmission
.
Front
suspension
and
steering
linkages,
inspecting
Inspection
of
the
front
suspension'and
steering
includes
a
check
of
all
moving
parts
for
wear
and
excessive
play
.
Also
in-
spect
the
rubber
seals
and
boots
for
cracks
or
tears
that
could
allow
the
entry
of
dirt,
water,
and
other
contaminants
.
See
310
Front
Suspension
.
Exhaust
system,
inspecting
Rear
suspension,
inspecting
Exhaust
system
life
varies
widely
according
to
driving
habits
Final
drive
and
rear
drive
axle
service
consists
of
checking
and
environmental
conditions
.
If
short-distance
driving
pre-
and
changing
the
gear
oil,
inspecting
for
leaks,
and
checking
dominates,
the
moisture
and
condensation
in
the
system
will
the
rear
drive
axle
rubber
boots
for
damage
.
not
fully
dryout
.
This
will
lead
to
early
corrosion
damage
and
more
frequent
replacement
.
The
areas
where
leaks
are
most
likely
to
occur
are
around
the
driveshaft
and
drive
axle
mounting
flanges
.
For
more
infor
Scheduled
maintenance
of
the
exhaust
system
is
limitedlo
mation
on
ídentifying
oil
leaks
and
their
causes,
see330
Rear
inspection
.
Check
for
restrictions
due
to
dents
or
kinks
.
Check
Suspension
.
for
weakness
or
perforation
due
to
rust
.
Check
lo
see
that
all
the
hangers
are
in
place
and
properly
supporting
the
system
and
that
the
system
does
not
strike
the
body
.
Alignment
of
the
sys-
Final
drive
oil
leve¡,
checking
temand
the
location
of
the
hangers
aredescribed
in
180
Ex-
haust
System
.
Check
the
lubricant
leve¡
with
thecar
level
.
Remove
the
oil
filler
plug
.
The
leve¡
is
correct
when
the
fluidjust
reaches
the
edge
of
the
filler
hole
.
Install
and
tighten
the
oil
filler
plug
when
Manual
Transmission
Service
the
oil
level
is
correct
.
See
Fig
.
26
.
Manual
transmissionservice
consists
of
inspectingfor
leaks
The
final
drive
should
be
filled
with
a
special
BMW
lubricant
and
checking
and
changing
the
fluid
.
available
through
an
authorized
BMW
dealer
.
In
addition,
the
lubricant
type
varies
depending
onwhether
or
nota
limited-slip
Evidence
of
transmissionleaks
is
fkely
to
beseenaround
the
differential
is
fitted
.
driveshaft
mounting
flange
and
at
the
bottom
of
the
bellhousing
.
For
more
information
on
identifying
oil
leaks
and
their
causes,
see230ManualTransmissionand210
Clutch
.
Tightening
Torque
"
Finaldrive
filler
plug
to
final
drive
housing
..................
70
Nm
(52
ft-Ib)
100-6
ENGINE-GENERAL
Cylinder
compression,
checking
A
compression
tester
is
needed
to
make
a
compression
test
.
To
obtain
accurate
test
results,
the
battery
and
starter
must
be
capable
of
cranking
the
engine
at
250-300
rpm,
and
theen-
gine
should
be
at
normal
operating
temperature
.
Use
com-
pressed
air
to
clean
aroundthe
spark
plugs
before
removal
.
1
.
Disable
the
ignítion
system
by
removing
the
engine
management
system
main
relay
and
the
fuel
pump
re-
¡ay
.
See
Fig
.
6
.
WARNING
-
The
ignítion
system
produces
high
voltages
that
canbe
fatal
.
Avoid
contact
with
exposed
termínals
and
useextreme
caution
when
working
on
acar
wíth
the
ignítion
switched
on
or
the
engine
running
.
Fuel
DM
E
pump
main
re
ay
rel
ay
o
oa
ooa
.,
o00
oao
Fig
.
6
.
Engine
management
relays
in
power
distribution
box
inleft
rear
of
engine
compartment
.
CAUTION-
"
On
OBD
11
cars,
making
a
compression
test
may
causea
faultto
set
in
the
ECM
and
may
also
il-
luminate
the
Check
Engine
light
.
The
light
can
only
be
tumed
out
using
special
scan
tool
equip-
ment,using
eíther
the
BMW
specialservíce
tool
or
using
a
"generic"
OBD
11
scan
tool
.
Discon-
necting
the
battery
will
not
erase
the
fault
mem-
orynor
turn
outthe
light
.
0013034,
0012630
Fig
.
7
.
Remove
spark
plug
wires
from
spark
plugs
on
4-cylinder
en-
gine
using
special
tool
.
Tool
is
stored
under
cover
at
rear
of
cylinder
head
(arrow)
.
Fig
.
8
.
Remove
engine
cover
on
6-cylinder
engine
byprying
off
nut
covers
and
removing
nuts
(A)
.
Be
careful
not
to
let
rubber
in-
sulators
fall
off
as
cover
is
removed
(arrows)
.
4
.
On
6-cylinder
engines,
disconnect
the
harness
connec-
tors
from
the
ignítion
coils
by
lifting
the
retaining
clip
.
Remove
the
coil
mounting
nuts
andremove
the
six
coils
.
See
Fig
.
9
.
Remove
the
sparkplugs
.
"
Failure
to
remove
the
main
relay
or
attempting
to
disable
the
ignítion
system
by
other
methods
may
resultin
damage
to
the
engine
control
module
.
NOTE-
Used
sparkplugs
should
be
reinstalled
in
the
same
cyl-
2
.
On
4-cylinder
engine
:
Remove
plastic
engine
cover
from
inder
fromwhich
they
were
removed
.
top
of
cylinder
head
.
Disconnect
spark
plug
wires
and
re-
move
spark
plugs
.
See
Fig
.
7
.
5
.
Insta¡¡
the
compression
gauge
in
the
first
cylinder's
3
.
On
6-cylinder
engine
:
Remove
top
engine
coverby
pry-
spark
plug
hole,
tight
enough
to
form
a
good
seal
.
ing
off
nut
covers
and
removing
mounting
nuts
.
See
Fig
.
8
.
MECHANICAL
TROUBLESHOOTING
eiioo4
Fig
.
9
.
Remove
ignition
coils
on
6-cylinder
engine
by
disconnecting
harness
connector
and
removing
mounting
bolts
(arrows)
.
NOTE-
"
The
compression
gauge
reading
shoutd
increase
with
each
compression
stroke
and
reach
near
its
maxi-
mum
reading
in
about
4-6
strokes
.
"All
cylinders
shoutdreach
maximum
compression
in
the
same
number
of
strokes
.
If
a
cylinder
needs
sig-
nificantly
more
strokes
to
reach
maximum
compres-
sion,
there
is
a
problem
.
7
.
Release
the
pressure
at
the
compression
gauge
valve,
then
remove
the
gauge
from
the
spark
plughole
.
Re-
peat
the
test
for
each
of
the
other
cylinders
and
com-
pare
the
results
with
the
values
given
below
.
ENGINE-GENERAL
1
:00-
7
Compression
Pressure
"
Minimum
..........
.
.
..
..
10-11
bar
(142-156
psi)
"
Maximum
difference
between
cylinders
..
.....
.........
0
.5
bar
(7
psi)
Reinstall
the
spark
plugs
and
spark
plug
wires
or
ignition
cofs
.
The
remainder
of
installation
is
the
reverse
of
removal
.
Be
sure
to
reihstall
al¡
wires
disconnected
during
the
test,
especial-
¡y
ground
wires
at
the
coils
and
cylinder
head
cover
(where
ap-
plicable)
.
Tightening
Torque
"
Spark
plug
to
cylinder
head
.......
25
Nm
(18
ft-Ib)
Low
compression
indicates
a
poorly
sealed
combustion
6
.
With
the
parking
brake
set,
the
transmission
in
Park
or
chamber
.
Relatively
even
pressures
that
are
below
specification
Neutral,
and
the
accelerator
pedal
pressed
to
the
floor,
normally
indicate
worn
piston
rings
and/or
cylinder
walls
.
Erratic
crank
the
engine
with
the
starter
.
Record
the
highest
values
tend
to
indicate
valve
leakage
.
Dramatic
differences
be
value
indicated
by
the
gauge
.
tween
cylinders
are
often
the
sign
of
a
failed
head
gasket,
bumed
valve,
or
broken
piston
ring
.
Engine
Mechanical
Troubleshooting
Table
Table
c
lists
the
symptoms
of
common
engine
mechanical
problems,
their
probable
causes
and
the
suggested
corrective
actions
.
The
bold
type
indicates
the
repair
groups
where
appli-
cable
test
and
repair
procedures
can
befound
.
MECHANICAL
TROUBLESHOOTING
100-8
ENGINE-GENERAL
Symptom
1
Probable
cause
and
correctiveaction
1
.
Engine
will
not
start
or
run
.
Starter
cranks
a
.
No
fuel
reaching
engine
.
Check
forfuelin
tank
.
engine
at
normal
speed
.
Fuel
pump
notoperating
.
Repair
Group
160
b
.
No
spark
.
Check
ignition
system
.
Repair
Group
120
c
.
Incorrect
valve
timing
.
Check
timing
chain
.
Repair
Group
117
2
.
Check
Engine
warning
light
illuminated
.
a
.
DME
engine
management
system
self-diagnostic
fault
detected
.
Sea
an
authorized
BMW
dealer
or
other
qualified
shop
for
OBD
II
fault
code
diagnosis
.
See
also
On-
board
Diagnostics(OBD),
given
later
inthis
repair
group
.
3
.
White
exhaust
smoke
(steam)
.
a
.
Failed
cylinder
head
gasket
(probably
accompanied
bylowcompression
readings)
.
Replace
gasket
and
resurface
cylinder
head
if
necessary
.
Repair
Group
113
4
.
Blue-gray
exhaust
smoke
and
oily
spark
a
.
Contaminated
or
gasoline-diluted
engine
oil
.
Change
engine
oil
and
replace
oil
filter
.
plugs
.
Indicates
oii
burning
in
combustion
.
Repair
Group
020
b
.
Faulty
valve
guide
seals
or
valve
guides
.
Replace
valve
guide
oil
seals
or
overhaul
cylinder
head
.
Repair
Group
116
5
.
Pinging
or
rattling
when
under
load,
a
.
Ignition
timing
too
advanced
.
Ignition
knocksensors
faulty
(CheckEngine
light
traveling
uphill,
or
accelerating,
especially
illuminated)
.
Repair
Group
120fromlow
speeds
.
Indicates
pre-ignition
or
b
.
Fuel
octane
leve¡
toolow
.
detonation
.
c
.
Engine
running
too
hot
or
overheating
.
Check
cooling
system
.
Repair
Group
170
6
.
Light
metallic
tapping
that
varies
directly
with
engine
speed
.
Oil
pressure
warning
light
not
illuminated
.
7
.
Light
metallic
knock
that
varies
directly
with
enginespeed
.
Oil
pressure
warning
light
blinking
or
fully
illuminated
;
may
be
most
noticeable
during
hard
stops
or
cornering
.
8
.
Screeching
or
squealing
under
load
that
a
.
Loose,worn,
or
damaged
drive
belt
.
Inspect
belt(s)
.
Repair
Group
020
goesaway
when
coasting
.
9
.
Growling
or
rumbling
that
varieswith
engine
a
.
Remove
drive
belt(s)toidentifyfaulty
component
.
Check
for
play,
bearing
roughness,
rpm
.
Indicates
abad
bearing
or
bushing
in
and
loose
mountings
.
Refer
to
appropriate
repair
group
for
repair
procedures
.
an
engine-driven
accessory
.
DRIVEABILITY
TROUBLESHOOTING
On-Board
Diagnostics
(OBD)
On-Board
Diagnostics
is
incorporated
into
al¡
engine
man-
Two
generations
of
OBD
are
usedon
thecars
covered
by
agement
systems
used
on
the
cars
covered
by
this
manual
.
this
manual
:
Therefore,
checking
for
fault
codes
should
be
the
first
step
in
troubleshootinga
driveability
problem
.
For
additional
informa-
On-Board
Diagnostics
tion
on
engine
management
and
repair
see130
Fuel
Injec-
tion
.
"
1992-1995models
....
.
..
....
.
..
.......
OBD
I
"
1996-1998models
.
....
..
.
.
.
..
.
........
OBD
II
DRIVEABILITY
TROUBLESHOOTING
Tablec
.
Engine
Mechanical
Troubleshooting
b
.
Warped
or
cracked
cylinder
head
.
Resurface
or
replace
cylinder
head
.
Repair
Group
113
c
.
Cracked
cylinder
block
.
Replace
engine
or
short
block
.
c
.
Worn
piston
rings
.
Overhaul
or
replace
engine
.
d
.
Failed
cylinder
head
gasket
.
Replace
gasket
.
Repair
Group
113
d
.
Air/fuel
mixture
too
lean
(Check
Engine
light
illuminated)
.
Repair
Group
130
a
.
Valveclearances
excessive
.
Check
hydraulic
valve
adjusters
.
Repair
Group
116
b
.
Low
oil
pressure
orpossibly
defective
warning
light
circuit
.
Check
oil
pressure
andwarning
light
circuit
.
Repair
Group
119
c
.
Dirty
oil
.
Change
oil
.
Repair
Group
020
.
a
.
Low
oil
leve¡
.
Check
and
correct
oil
leve¡
.
b
.
Low
oil
pressure/worn
or
faulty
oil
pump
.
Oil
pump
pickup
restricted/clogged
.
Check
oil
pressure
.
Repair
Group
119
The
OBD
system
detects
emissions-related
engine
manage-
ment
malfunctions
and
tucos
on
the
Check
Engíne
lightin
the
in-
strument
cluster
.
TheCheck
Engine
light
will
stay
on
until
the
code(s)are
called
up
and
the
memory
is
erased
.
When
faulty
are
detected,
the
OBD
system
stores
a
Diagnostic
Trouble
Code
(DTC)
in
the
system
ECM
.
In
addition,
the
Check
Engine
warn-
ing
light
will
come
on
if
an
emissions-related
fault
is
detected
.
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
.
110-2
ENGINE
REMOVAL
AND
INSTALLATION
8
.
Drain
engine
coolant
andremove
coolant
hoses
at-
10
.
Remove
radiator
cooling
fan
and
radiator
as
described
tached
to
cylinder
head
.
in
170
Radiator
and
Cooling
System
.
"
Drain
radiator
and
engine
block
.
See
170
Radiator
and
Cooling
System
.
NOTE-
"
Disconnect
hoses
from
thermostat
housing
at
front
of
Some
late
4-cylinder
modelsuse
an
electric
prímary
cylinder
head
.
cooling
fan
.
"
Disconnect
heater
hoses
at
rear
of
engine
.
See
Fig
.
2
.
CAUTION-
NOTE-
On
cars
with
viscous-type
cooling
fans,
the
radia-
"
The
block
drain
plug
is
located
on
the
exhaust
side
to-
tor
fan
has
left
hand
threads
.
wards
rear
of
engine
.
"
Remove
small
plastic
lock
clíp
to
pull
radiator
drain
11
.
Remove
upper
intake
manifold,
unfasten
cable
duct
plug
out
completely
.
from
lower
intake
manifold,
crankcase
vent
valve
hose
(M44
engine
only)
0012687
Fig
.
2
.
Coolant
hoses
at
heater
valve
and
heatercore
to
be
discon-
nected
(arrows)
.
9
.
Remove
air
shroud
from
top
of
radiator
.
See
Fig
.
3
.
ENGINE
REMOVAL
AND
INSTALLATION
12
.
Disconnect
fuel
supply
and
fuel
return
lines,
main
en-
gine
electrical
connectors,
and
lower
intake
manifold
as
described
in
113
Cylinder
HeadRemoval
and
Instal-
lation
.
See
Fig
.
4
.
0012504
Fig
.
4
.
Crankcase
ventvalve
(A)
on
top
of
lower
intake
manifoldof
M44
engine
.
Fueldelivery
and
retum
lines
shown
at
B
.
Engine
harness
and
sensor
connectors
shown
at
C
.
WARNING
-
"
Fuel
may
be
expelled
under
pressure
.
Do
not
smoke
orworknear
heaters
or
other
fire
haz-
ards
.
Keep
a
fire
extinguisher
handy
.
Before
dis-
connecting
fuel
hoses,
wrap
a
cloth
around
fuel
hoses
to
absorb
any
leaking
fuel
.
Plug
all
open
fuel
lines
.
"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
lines
.
CAUTION-
0013137
I
Stuff
clean
rags
into
the
open
intake
ports
topre-
Fig
.
3
.
Front
air
shroud
mounting
screws
(arrows)
.
vent
any
parts
from
falling
into
the
engine
intake
.
13
.
Disconnect
vacuum
hose
from
brake
booster
on
bulk-
head
.
Cover
bothhole
in
booster
and
plug
hose
end
.