1987 TOYOTA CELICA Service Repair Manual

EFI SYSTEM - Troubleshooting
FI-1 E
CONTINUED FROM PAGE FI-14 ._
CHECK FUEL SUPPLY TO INJECTOR
1. Fuel in tank
2. Fuel pressure in fuel line
(1) Short terminals +B and FP of the
check connector.
(2) You can feel fuel pressure in fuel
return hose. BAD 1. Fuel line - leakage - deformation
2. Fuse
3. Fuel pump (See age FI-73)
4. Fuel filter
5. Fuel pressure regulator (See. page FI-84)
6. Circuit opening relay (See page FI-1 13)
3. Check circuit opening relay
(See page FI-1 13)
OK
CHECK FUEL PUMP SWITCH IN AIR
FLOW METER (7M-GE)
Check continuity between terminals FP and
El with measuring plate of,air flow meter
,,’
open.
L
I BAD c
Air flow meter (See page FL96)
I OK
CHECK IGNITION TIMING
1. Short terminals T(MA) or TEl (MS) and
El of the check connector.
2. Check ignition timing.
STD: 10’ BTDC @ Idle
short circuited TIMA) or
3
I OK NO Adjust ignition timing (See page EM-l 7)
BAD 1. Wiring connection
2. Power to ECU
(1) .Fusible links
(2) Fuses
(3) EFI main relay
3. Air flow meter
4. Water temp. sensor
5. Air temp. sensor
6. Injection signal circuit
(1) Injector wiring

l-16 EFI SYSTEM - Troubleshooting
SYMPTOM - ENGINE OFTEN STALLS
CHECK DIAGNOSIS SYSTEM
Check for output of diagnostic code.
(See page Fl-26) * Diagnostic code(s) (See pages FI-30, 31, 32)
Malfunction
code(s)
Normal code
CHECK FOR VACUUM LEAKS IN AIR
INTAKE LINE BAD 1. Oil filler cap
2. Oil level gauge
3. Hose connections
4. PCV hose
I OK
CHECK FUEL SUPPLY TO INJECTOR
‘*-- Fuel in tank BAD
L. Fuel pressure in fuel line
(1) Short terminals +B and FP of the check
connector.
(2) You can feel fuel pressure in fuel
return hose. .
3. Check circuit opening relay
(See page FI-113) .
1. Fuel line - leakage - deformation
2. Fuse
3. Fuel.pump (See’ page FI-73)
4. Fuel filter
5. Fuel pressure regulator (See page FI-84)
6. Circuit opening relay (See page FI:1 13).
,
OK
CHECK AIR FILTER
I BAD Element - Clean or replace
OK
CHECK IDLE SPEED
STD: 7M-GE wl TWC 700 rpm
7M-GE w/o TWC 800 rpm
7M-GTE 800 rpm
t w
BAD ISC system
(I 1 Wiring connection
(21 ISC valve
(3) ECU
CHECK IGNITION TIMING ‘-
‘I. Short terminals TiMA) or TEl (MS) and
El of the check connector..
2. Check ignition timing.
STD: 10” BTDC @ Idling
short circuited T(MA) or
1
OK
CHECK SPARK PLUGS
Plug gap:
7M-GE Conventional Tipped Type
0.8 mm (0.031 in.)
7M-GE Platinum Tipped Type
1.1 mm (0.043 in.)
7M-GTE
0.8 mm (0.031 in.)
NOTE: Check compression pressure and
-I------- :+ -nyrpCCpn, c
NO
-I-
BAD - Adjust ignition timing. (See page EM-1 7)
1. Spark plugs
2. Compression pressure
Limit: 9.0 kg/cm2 (128 psi, 883
kPa)
at 250 rpm
3. Valve clearance (Cold)
STD: IN 0.15 - 0.25 mm
(0.06 - 0.010 in.)

EFI SYSTEM - Troubleshooting
OK ‘. .CONTINUED FROM PAGE FI-I 6
m
CHECK COLD START INJECTOR
1. Cold start injector
(See page FI-80) BAD
2. Cold start injector time switch
(See page FL11 5)
OK FI-17
CHECK FUEL PRESSURE
(See page FI-74) BAD p 1. Fuel pump (See page FL73)
2. Fuel filter
3. Fuel pressure regulator (See page FI-84)
OK
CHECK INJECTORS
(See page FI-86) c
-
BAD Injection condition
I OK
..I
’ CHECK EFI ELECTRONIC CIRCUIT
USING VOLT/OHMMETER
(See pages FI-34, 57) BAD 1. Wiring connection
2. Power to ECU
(I) Fusible links
(2) Fuses
(3) EFI main relay
3. Air flow meter
4. Water temp. sensor
5. Air temp. sensor
6. Injection signal circuit
(I 1 Injector wiring
SYMPTOM - ENGINE SOMETIMES STALLS
I
CHECK DIAGNOSIS SYSTEM
Check for output of diagnostic code.
‘I ,. ,dSee page FI-26)
I Normal code
I
CHECK AIR FLOW METER’
Air flow meter
(See pages .Fl-96, 98)
I
OK
CHECK WIRING CONNECTORS AND
RELAYS 1 BAD --
2’ EFI main relay (See page FI 112)
Check for a signal change when the connec- 3. Circuit opening relay (See page FI-113)
tor or relay is slightly tapped or wiggled.

a EFI SYSTEM - Troubleshooting
SYMPTOM - ROUGH IrIiLlNG AND/OR MISSING
iECK DIAGNOSIS SYSTEM
leek for output of diagnostic code.
ee page FI-26)
1 -c Diagnostic code(s) (See pages FI-30, 31, 32)
Malfunction
code(s)
Normal code
HECK FOR VACUUM LEAKS IN’AIR
d-FAKE LINE
I OK’
If* “K AIR FILTER
ELEMENT Element - Clean or replace
I
I 1, Oil filler cap
2. Oil level gauge
3. Hose connections
4. PCV hose
5. EGR system - EGR vaive stays open (EGR)
OK
CHECK IDLE SPEED
STD: 7M-GE w/ TWC 700 rpm
7M-GE w/o TWC 800 rpm
7M-GTE
800 rpm
OK
,
BAD SC system
(1) Wiring connection
(2) ISC valve
(3) ECU
CHECK IGNITION TIMING
1, Short terminals T(MA) or TEI (MS) and
El of the check connector.
2. Check ignition timing.
STD: IO” BTDC @ Idling
w/ short circuited T(MA)
I TEl(MS1 - El NO F Adjust ignition timing. (See page EM-l 7)
i OK
‘.
7
I
CHECK SPARK PLUGS
Plug gap:
7M-GE Converitional Tipped Type
0.8 mm (0.031 in.)
7M-GE Platinum Tipped Type
1.1 mm (0,043 in.)
7M-GTE
0.8 mm (0.031 in.)
NOTE: Check compression pressure and
valve clearance if necessary.
OK CONTINUED ON PAGE FI-19 BAD 1. Spark plugs
2. Compression pressure
Limit: 9.0 kg/cm2 (128 psi, 883
kPa)
at 250 rpm
3. Valve clearance (Cold)
STD: IN 0.15 - 0.25 mm
(0.08 - 0.010 in.)
EX 0.20 - 0.30 mm
(0.008 - 0.012 in.)

EFI SYSTEM - Troubleshooting
FI-19
CONTINUED FROM PAGE Fl-18 ._
t
CHECK COLD START INJECTOR *
(See page FI-80) BAD 1. Cold start injector
2. Cold start injector time switch
(See page FL11 5)
CHECK FUEL PRES$URE
(See page FL74) BAD c 1. Fuel pump (See page FI-73)
2. Fuel filter
.3. Fuel pressure regulator (See page FI-84)
I
I 1 c 4
/OK
I
CHECK INJECTORS
(See page FI-86) 8AD * Injection condition
I OK
L 1
ZHECK EFI ELECTRONIC CIRCUIT
USING VOLT/OHMMETER
(See pages FL34, 57) c
BAD 1. Wiring connection
2. Power to ECU
\‘l’, F;t;e links
(3) EFI main relay
3. Air flow meter
4. Water temp. sensor
5. Air temp. sensor
6. Throttle position sensor
7. Injection signal circuit
(1) injector wiring

.20 EFI SYSTEM - Troubleshooting __
SYMPTOM - HIGH ENGINE IDLE SPEED (NO DROP)
:HECK ACCELERA
OK
CHECK POWER STEERING !DLE+JP
SYSTEM
OK .
‘:
j..l.
CHECK DIAGNOSIS SYSTEM
Check for output of diagnostic code.
(See page FI-26) ‘:.
_T I Linkage - Stuck
I
9
BAD * Air valve
I
r
* Diagnostic code(s) (See pages FI-30, 31, 32)
Malfunction
..
code!s)
Normal code
.
CHECK ISC SYSTEM
BAD
I
OK
71
(Air con Throttle posrtron sensor - ECU)
1 CHECK THROTTLE POSITION SENSOR
t-x- Throttle body
OK
CHECK FUEL PRESSURE
(See page FI-74) 7
BAD w Fuel pressure regulator - High pressure
OK
CHECK COLD START INJECTOR
~ .ee page FI-80) BAD w Cold start injector - Leakage
CHECK INJECTORS (See page FI-86)
I Injectors - Leakage, Injection quality
I OK
CHECK EFI ELECTRONIC CIRCUIT USING
VOLT/OHMMETER
(See pages FI-34, 57) BAD - 1. Wiring connection
2. Power to ECU
(1) Fusible links
(2) Fuses
(3) EFI main relay
3. Air flow meter
4. Water temp. sensor
5. Air temp. sensor
6. Injection signal circuit
(1) Injector wiring
(2) Resistor
(3) ECU

EFI SYSTEM - Troubleshooting
FI-21
-.
SYMPTOM - ENGINE BACKFtRES-Lean Fuel Mixture
CHECK DIAGNOSIS SYSTEM
Check for output of diagnostic code
(See page FI-26) Malfunction --) Diagnostic code(s) (See pages FI-30, 31, 32)
.code 1s) j
,
Normal code
CHECK FOR VACUUM LEAKS IN AIR
INTAKE LINE
1. Short terminals T(MA) or TEl (MS) and BAD -
NO 1. Oil filler cap
2. Oil dipstick
3. Hose connections
4. PCV hose
Adjust ignition timing. (See page EM-1 7)
1. Cold start injector
2. Cold start injector time switch
(See page FI-115)
CHECK FUEL PRESSURE
(See page FI-74)
I
I
BAD 1. Fuel pump (See page‘ FI-73)
2. Fuel filter
3. Fuel pressure regulator (See page Fl-84)
I
’ “,HECK INJib
‘I- See page FI-86)’ - Injectors - Clogged
BAD
. ., .l
I OK
CHECK Eii ELECTRONIC ClR&lT
USING VOLT/OHMMETER
(See pages FI-34, 57)
4
BAD 1. Wiring connection
2. Power to ECU
(1) Fusible links
(2) Fuses
(3) EFI main relay
3. Air flow meter
4. Water temp. sensor
5. Air temp. sensor
6. Throttle position sensor
7. Injection signal circuit
(1) Injector wiring
Ii, zesstor
(4) Fuel cut signal
8. Oxygen sensor

Ii-22 EFI SYSiiM - Troubleshooting
SYMPTOM - MUFFLER EXPLOSION (AFTER FIRE)
-Rich Fuel Mixture-Misfire
CHECK DIAGNOSIS SYSTEM
Check for output of diagnostic code
(See page FI-26) pm Diagnostic code(s) (See pages Fl-30, 31, 32)
Malfunction
code(s)
4
c
Normal code
CHECK IGNITION TIMING
1. Short terminals TiMA) or TEl (MS) and
El of the check connector.
2. Check ignition timing.
STD: IO” BTDC @ Idling
w/ short circuited TfMA) or
C TEl(MS) - El I
OK NO
BAD
I-
Adjust ignition timing. (See page EM- 17)
I
1. Cold start injector
2. Cold start injector time switch
(See page FI- 115)
1
CHECK INJECTORS
BAD injector - Leakage
I
I OK
CHECK SPARK PLUGS
Plug gap:
7M-GE Conventional .Tipped Type
0.8 mm (0.031 in.)
7M-GE Platinum Tipped Type
1.1 mm (0.043 in.)
7M-GTE
0.8 mm (OiO31 in.)
NOTE: Check compression pressure and
valve clearance if necessary.
OK
CHECK EFI ELECTRONIC CIRCUIT USING
VOLT/OHMMETER
(See pages Fl-34, 57) NO
BAD - 1. Spark plugs
2. Compression pressure
Limit: 9.0 kg/cm2 (128 psi, 883
kPa)
at 250 rpm
3. Valve clearance (Cold)
STD: IN 0.15 - 0.25 mm
(0.06 - 0.010 in.)
EX 0.20 - 0.30 mm
(0.006 - 0.012 in.)
i
1. Throttle position sensor
2. Injection signal circuit
(I) Injector wiring
(2) Resistor
(3) ECU
3. Oxygen sensor