1997 TOYOTA SUPRA check engine

15
C TROUBLESHOOTING
DISCONNECTION AND CONNECTION OF BOLT
TYPE CONNECTORS
For engine control module in this vehicle, connections are used
which require a bolt built into the connector to be screwed down
to securely connect the connector.
1. Disconnect the connector
After completely loosening the bolt, the two parts of the
connector can be separated.
NOTICE:
Do not pull the wire harness when disconnecting the
connector.
2. Connect the connector
NOTICE:
Before connecting the connector, always check that
the terminals are not bent or damaged.
(a) Match the guide section of the male connector
correctly with the female connector, then press
them together.
(b) Tighten the bolt.
Make sure the connectors are completely
connected, by tightening the bolt until there is a
clearance of less than 1 mm (0.04 in.) between the
bottom of male connector and the end of female
connector.

15A
HEAD (
RH)
(
USA)
25
6
1
IF2 13 IF1 6IB1 2
IF2 1IF24IF114
IE1 1IE12IE13
BP1 5 BP13BP11 II1 24 II1 19 A 2A 16 A15 B6
A 7A6A3A9A8B8A10 A11 A13
II1 29
SLIP
CRUISE
HIGH BEAM
WATER TEMP.
FUEL
FUEL
TACHO
IJ213
IE EC IFI 3 FROM POWER SOURCE SYSTEM (
SEE PAGE 56)
IJ29
EXT
I 4
E10
C 9
P 2
COMBINATION METER FROM HEADLIGHT HI RH
FUEL SENDERIGNITER
ENGINE CONTROL MODULE
CLUTCH START
SW
PARK/NEUTRAL POSITION
SW Y- G
Y- B
BR BRY- B Y- GBR Y- RR- LO W
Y- G
Y- B
BR
B- W B- W
B- W BRBR Y- L (
*3) R- L W- BW
O TO THROTTLE E CU
TO CRUISE CONTROL
ECU
TO DI MME R SW
[COMB. SW]
ENGINE COOLANT TEMP. SENDER
LH
RH TURNB
(
A/T)
B
(
M/T)B- W
(
M/T) R- W
(
*1)
B- W
G- B
G- Y R- W R- W
R- W
G- B
G- YB- WB
B BR
BR
(
*4)
(
*3) (
*1)
BULB
CHECK RELAY
123416FROM TURN SIGNAL SW
[COMB. SW]
1 2
(
*2)
E 4
C
C10 , C11
, C1 2
BA
(
*3)
1I 4
B (
*3)
Y- R (
*4)
(
A/ T)
(
A/T)(
A/T) (
*2)
TACO
F14
2
P
N
1E 19 1E14 1H 11 1H7
7. 5A
ST
1K 4
220
COMBINATION METER

S02980
FilterCap
S02981
Vacuum Gauge
EC047-02
- EMISSION CONTROL (2JZ-GTE)EXHAUST GAS RECIRCULATION (EGR) SYSTEM
EC-7
1244 Author
: Date
:
1997 SUPRA (RM502U)
EXHAUST GAS RECIRCULATION
(EGR) SYSTEM
INSPECTION
1. CHECK AND CLEAN FILTER IN EGR VACUUM
MODULATOR
(a) Remove the cap and 2 filters.
(b) Check the filter for contamination or damage.
(c) Using compressed air, clean the filter.
(d) Reinstall the 2 filters and cap.
HINT:
Install the filter with the coarser surface facing the atmospheric
side (outward).
2. INSTALL VACUUM GAUGE
Using a 3-way connector, connect a vacuum gauge to the hose
between the EGR valve and EGR vacuum modulator.
3. INSPECT SEATING OF EGR VALVE
Start the engine and check that the engine starts and runs at
idle.
4. INSPECT VSV OPERATION WITH COLD ENGINE
(a) M/T
The coolant temperature should be below 50°C (122°F).
(1) Start the engine and check idling.
(2) When idling with the lever shifting in the N position,
press accelerator pedal slowly to hold the engine
speed at 1,600 - 1,800 rpm.
(3) Check that the vacuum gauge indicates zero.
(b) A/T
The coolant temperature should be below 65°C (149°F).
(1) Chock the 4 wheels.
(2) Fully apply the parking brake.
(3) Connect a tachometer to the engine.
(4) Start the engine and check idle.
(5) Keep your foot pressed firmly on the brake pedal.
(6) Shift into the D position. Press the accelerator pedal
slowly to hold the engine speed at 1,600 - 1,800
rpm.
(7) Check that the vacuum gauge indicates zero.
5. INSPECT VSV OPERATION WITH HOT ENGINE
(a) M/T
Warm up the engine. The coolant temperature in 50°C
(122°F) or more.
(1) When idling with the lever shifting in the N position,
press accelerator pedal slowly to hold the engine
speed at 1,600 - 1,800 rpm.
(2) Check that the vacuum gauge indicates low vacu-
um momentarily.

S02982
To Intake
Manifold
S02983
Engine Stopped
Air PQ
S02984
Engine at
3,500 rpm
Air PQ EC-8
- EMISSION CONTROL (2JZ-GTE)EXHAUST GAS RECIRCULATION (EGR) SYSTEM
1245 Author
: Date
:
1997 SUPRA (RM502U)
(b) A/T
Warm up the engine. The coolant temperature in 65°C
(149°F) or more.
(1) Chock the 4 wheels.
(2) Fully apply the parking brake.
(3) Connect a tachometer to the engine.
(4) Start the engine and check idling.
(5) Keep your foot pressed firmly on the brake pedal.
(6) Shifting into the D position. Press the accelerator
pedal slowly to hold the engine speed at 1,600 -
1,800 rpm.
(7) Check that the vacuum gauge indicates low vacu-
um.
6. REMOVE VACUUM GAUGE
Remove the vacuum gauge, and reconnect the vacuum hoses
to their proper locations.
7. INSPECT EGR VALVE
(a) Apply vacuum directly to the EGR valve with the engine
idling.
(b) Check that the engine runs rough or dies.
(c) Reconnect the vacuum hoses to their proper locations.
If no problem is found during this inspection, system is normal;
otherwise inspect each part.
8. INSPECT VSV FOR EGR
(See page SF-69)
9. DISCONNECT VACUUM HOSES FROM EGR VACUUM
MODULATOR
Disconnect the 2 vacuum hoses from ports P and Q of the EGR
vacuum modulator.
10. INSPECT EGR VACUUM MODULATOR OPERATION
(a) Block port P with your finger.
(b) Blow air into port Q, and check that air passes through to
the air filter side freely.
(c) Start the engine, and maintain speed at 3,500 rpm.
(d) Repeat the above test. Check that there is a strong resis-
tance to air flow.
11. RECONNECT VACUUM HOSES TO EGR VACUUM
MODULATOR
Reconnect the 2 vacuum hoses to the proper locations.

P02129
Z09528
P02136
EM0580
EM-36
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1141 Author
: Date
:
1997 SUPRA (RM502U)
5. CLEAN CYLINDER HEAD
Using a soft brush and solvent, thoroughly clean the cylinder
head.
6. INSPECT FOR FLATNESS
Using precision straight edge and feeler gauge, measure the
surfaces contacting the cylinder block, intake and exhaust
manifolds for warpage.
Maximum warpage: 0.10 mm (0.0039 in.)
If warpage is greater than maximum, replace the cylinder head.
7. INSPECT FOR CRACKS
Using a dye penetrant, check the combustion chamber, intake
ports, exhaust ports and cylinder block surface for cracks.
If cracked, replace the cylinder head.
8. CLEAN VALVES
(a) Using a gasket scraper, chip off any carbon from the valve
head.
(b) Using a wire brush, thoroughly clean the valve.

Z02413
Z00052
Z00054
44.5°
EM0181
Margin Thickness
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
EM-37
1142 Author
: Date
:
1997 SUPRA (RM502U)
9. INSPECT VALVE STEMS AND GUIDE BUSHINGS
(a) Using a caliper gauge, measure the inside diameter of the
guide bushing.
Bushing inside diameter:
6.010 - 6.030 mm (0.2366 - 0.2374 in.)
(b) Using a micrometer, measure the diameter of the valve
stem.
Valve stem diameter:
Intake 5.970 - 5.985 mm (0.2350 - 0.2356 in.)
Exhaust 5.965 - 5.980 mm (0.2348 - 0.2354 in.)
(c) Subtract the valve stem diameter measurement from the
guide bushing inside diameter measurement.
Standard oil clearance:
Intake 0.025 - 0.060 mm (0.0010 - 0.0024 in.)
Exhaust 0.030 - 0.065 mm (0.0012 - 0.0026 in.)
Maximum oil clearance:
Intake 0.08 mm (0.0031 in.)
Exhaust 0.10 mm (0.0039 in.)
If the clearance is greater than maximum, replace the valve and
guide bushing.
10. INSPECT AND GRIND VALVES
(a) Grind the valve enough to remove pits and carbon.
(b) Check that the valve is ground to the correct valve face
angle.
Valve face angle: 44.5°
(c) Check the valve head margin thickness.
Standard margin thickness:
0.8 - 1.2 mm (0.031 - 0.047 in.)
Minimum margin thickness:
0.5 mm (0.020 in.)
If the margin thickness is less than minimum, replace the valve.

EM2534
Overall Length
EM0255
P02127
45°
Carbide
Cutter
Z00373
Width
P03966
45°
15°
Width EM-38
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1143 Author
: Date
:
1997 SUPRA (RM502U)
(d) Check the valve overall length.
Standard overall length:
Intake 98.29 - 98.79 mm (3.8697 - 3.8894 in.)
Exhaust 98.84 - 99.34 mm (3.8913 - 3.9110 in.)
Minimum overall length:
Intake 98.19 mm (3.8657 in.)
Exhaust 98.74 mm (3.8874 in.)
If the overall length is less than minimum, replace the valve.
(e) Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, resurface the tip with a grinder or
replace the valve.
NOTICE:
Do not grind off more than the minimum overall length.
11. INSPECT AND CLEAN VALVE SEATS
(a) Using a 45° carbide cutter, resurface the valve seats.
Remove only enough metal to clean the seats.
(b) Check the valve seating position.
Apply a thin coat of prussian blue (or white lead) to the
valve face. Lightly press the valve against the seat. Do not
rotate the valve.
(c) Check the valve face and seat for the following:

If blue appears 360° around the face, the valve is
concentric. If not, replace the valve.

If blue appears 360° around the valve seat, the
guide and face are concentric. If not, resurface the
seat.

Check that the seat contact is in the middle of the
valve face with the following width:
Intake 1.0 - 1.4 mm (0.039 - 0.055 in.)
Exhaust 1.2 - 1.6 mm (0.047 - 0.063 in.)
If not, correct the valve seats as follows:

If the seating is too high on the valve face, use 15°
and 45° cutters to correct the seat.

P04463
EM2011
EM2538
P02141
P02360
Plastigage EM-40
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1145 Author
: Date
:
1997 SUPRA (RM502U)
13. INSPECT CAMSHAFT FOR RUNOUT
(a) Place the camshaft on V-blocks.
(b) Using a dial indicator, measure the circle runout at the
center journal.
Maximum circle runout: 0.08 mm (0.0031 in.)
If the circle runout is greater than maximum, replace the cam-
shaft.
14. INSPECT CAM LOBES
Using a micrometer, measure the cam lobe height.
Standard cam lobe height:
Intake 44.570 - 44.670 mm (1.7547 - 1.7587 in.)
Exhaust 44.770 - 44.870 mm (1.7626 - 1.7665 in.)
Maximum cam lobe height:
Intake 44.42 mm (1.7488 in.)
Exhaust 44.62 mm (1.7567 in.)
If the cam lobe height is less than minimum, replace the cam-
shaft.
15. INSPECT CAMSHAFT JOURNALS
Using a micrometer, measure the journal diameter.
Journal diameter:
28.949 - 28.965 mm (1.1397 - 1.1404 in.)
If the journal diameter is not as specified, check the oil clear-
ance.
16. INSPECT CAMSHAFT BEARINGS
Check the bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cyl-
inder head as a set.
17. INSPECT CAMSHAFT JOURNAL OIL CLEARANCE
(a) Clean the bearing caps and camshaft journals.
(b) Place the camshafts on the cylinder head.
(c) Lay a strip of Plastigage across each of the camshaft jour-
nals.