EC−12
−
EMISSION CONTROL EXHAUST GAS RECIRCULATION (EGR) SYSTEM
1996 LAND CRUISER (RM451U)
HINT:
As a large amount of exhaust gas enters, the engine will misfire
slightly.
7. DISCONNECT TOYOTA HAND −HELD TESTER OR
OBD II SCAN TOOL
8. REMOVE VACUUM GAUGE
Remove the vacuum gauge, and reconnect the vacuum hoses
to the proper locations.
9. INSPECT EGR VALVE
(a) Apply vacuum directly to the EGR valve with the engine idle.
(b) Check that the engine runs rough or dies.
(c) Reconnect the vacuum hoses to the proper locations.
If no problem is found with this inspection, system is normal;
otherwise inspect each part.
10. CANCEL DIAGNOSTIC TROUBLE CODE
11. REMOVE AIR INTAKE CHAMBER (See page EM−28)
12. DISCONNECT VACUUM HOSES AND CONNECTOR
13. INSPECT VSV FOR OPEN CIRCUIT
Using an ohmmeter, check that there is continuity between the
terminals. Resistance: 30 − 34 Ω at 20° C (68°F)
If there is no continuity, replace the VSV.
14. INSPECT VSV FOR GROUND
Using an ohmmeter, check that there is no continuity between
each terminal and the body.
If there is continuity, replace the VSV.
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010
EM−2
−
ENGINE MECHANICAL CO/HC
505
Author: Date:
1996 LAND CRUISER (RM451U)
6. TROUBLESHOOTING
If the CO/HC concentration does not comply with regulations,
troubleshoot in the order given below.
See the table below for possible causes, and then inspect and
correct the applicable causes if necessary.
COHCProblemsCauses
NormalHighRough idle
3. Faulty ignitions:
Incorrect timing
Fouled, shorted or improperly gapped plugs
Open or crossed high −tension cords
Cracked distributor cap
4. Incorrect valve clearance
5. Leaky EGR valve
6. Leaky intake and exhaust valves
7. Leaky cylinders
LowHighRough idle
(Fluctuating HC reading)
1. Vacuum leaks:
PCV hose
EGR valve
Intake manifold
Air intake chamber
Throttle body
IAC valve
Brake booster line
2. Lean mixture causing misfire
HighHighRough idle
(Black smoke from exhaust)
1. Restricted air filter
2. Faulty SFI systems:
Faulty pressure regulator
Clogged fuel return line
Defective ECT sensor
Faulty ECM
Faulty injector
Faulty throttle position sensor
Faulty MAF meter
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010
SF1ED−04
−
SFI SFI SYSTEM
SF−1
629
Author: Date:
1996 LAND CRUISER (RM451U)
SFI SYSTEM
PRECAUTION
1. BEFORE WORKING ON FUEL SYSTEM, DISCON-
NECT NEGATIVE (−) TERMINAL CABLE FROM THE
BATTERY.
HINT:
Any diagnostic trouble code retained by the computer will be
erased when the negative ( −) terminal cable is disconnected.
Therefore, if necessary, read the diagnosis before disconnect-
ing the negative ( −) terminal cable from the battery.
2. DO NOT SMOKE OR WORK NEAR AN OPEN FLAME WHEN WORKING ON FUEL SYSTEM.
3. KEEP GASOLINE AWAY FROM RUBBER OR
LEA TH-
ER PARTS
4. MAINTENANCE PRECAUTIONS
(a) In event of engine misfire, these precautions should be taken.
(1) Check proper connection of battery terminals, etc.
(2) Handle high −tension cords carefully.
(3) After repair work, check that the ignition coil termi- nals and all other ignition system lines are recon-
nected securely.
(4) When cleaning the engine compartment, be espe-
cially careful to protect the electrical system from
water.
(b) Precautions when handling the oxygen sensor. (1) Do not allow the oxygen sensor to drop or hit
against an object.
(2) Do not allow the sensor to come in contact with wa- ter.
5. IF VEHICLE IS EQUIPPED WITH MOBILE RA-
DIO
SYSTEM (HAM, CB, ETC.)
If the vehicle is equipped with a mobile communication system,
refer to the precaution in the IN section.
6. AIR INDUCTION SYSTEM
(a) Separation of the engine oil dipstick, oil filler cap, PCV hose, etc. may cause the engine to run out of tune.
(b) Disconnection, looseness or cracks in the parts of the air
induction system between the throttle body and cylinder
head will allow air suction and cause the engine to run out
of tune.
7. ELECTRONIC CONTROL SYSTEM
(a) Before removing SFI wiring connectors, terminals, etc., first disconnect the power by either turning the ignition
switch OFF or disconnecting the negative ( −) terminal
cable from the battery.
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010
