Toyota COMPUTER-CONTROLLED SYSTEM - Page 165

TROUBLESHOOTING - Symptom Char t
SYMPTOM
POSSIBLE CAUS
E
SYSTEM
COMPONENT PART TYPE OF TROUBL E
Fuel pump
Drop in flow volum e
l t F
Injectors
Drop in injection volum e
e m ue sys
Pressure regulator
Fuel pressure too lo w
Fuel filter, fuel line
Clogge d
Igniter
Malfunctionin g
Hesitate s
during
Ignition system
Ignition coil
(poor contact )
acceleration
Spark plugs
Misfir e
Manifold pressur e
sensor (vacuum sensor)
e or resistanc e Volt a
Electronic control
Water temp. sensor
g
are incorrect, open o r
system
Intake air temp
. sensor
sho
rt
circui t
Thro tt le position senso
r
Oxygen (02) sensor Malfunctionin g
Fuel pump Drop in flow volum e
l
F t
Injectors Drop in injection volum
e
e
m
ue sys
Pressure regulator Fuel pressure too lo
w
Poor drivability
Fuel filter, fuel line Clogge d
Igniter
Malfunctionin
g
Ignition system Ignition coil
(poor contact
)
Backfiring Spark plugs
Misfir e
Manifold pressur e
sensor (vacuum sensor )
Electronic control
Water temp . sensor
Voltage or resistanc e
system
Intake air temp . sensor
are incorrec t
Thro tt le position senso r
Oxygen (02) sensor Malfunctionin g
Fuel system
Injectors Leakag e
Cold sta
rt
system
Cold sta
rt
injector
Leakage, inject s
continuousl y
Sta rt injector time SW Stays on continuousl
y
Afterfirin g
(muffler
Manifold pressur e
sensor (vacuum sensor)
Voltage or resistanc e
explosions)
Electronic control
Water temp. sensor
are incorrec t
system
Intake air temp . senso r
Thro
tt
le position sensor Idle contact won't go o
n
Oxygen (02) sensor Malfunctioning
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