leak SUZUKI JIMNY 2005 3.G Service Manual PDF

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Fuel pressure relief procedure
After making sure that engine is cold, release fuel pressure as fol-
lows.
1) Place transmission gear shift lever in “Neutral” (Shift selector
lever to “P” range for A/T model), set parking brake, and
block drive wheels.
2) Remove relay box cover.
3) Disconnect fuel pump relay (1) from its connector.
4) Remove fuel filler cap to release fuel vapor pressure in fuel
tank and then reinstall it.
5) Start engine and run it till it stops for lack of fuel. Repeat
cranking engine 2-3 times for about 3 seconds each time to
dissipate fuel pressure in lines. Fuel connections are now
safe for servicing.
6) Upon completion of servicing, connect fuel pump relay (1) to
its connector.
Fuel leakage check procedure
After performing any service on fuel system, check to make sure
that there are no fuel leakages as follows.
1) Turn ON ignition switch for 3 seconds (to operate fuel pump)
and then turn it OFF.
Repeat this (ON and OFF) 3 or 4 times and apply fuel pres-
sure to fuel line. (till fuel pressure is felt by hand placed on
fuel feed hose.)
2) In this state, check to see that there are no fuel leakages
from any part of fuel system. CAUTION:
This work must not be done when engine is hot. If done
so, it may cause adverse effect to catalyst.

Downloaded from www.Manualslib.com manuals search engine 6-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Visual inspection
Visually check following parts and systems.
INSPECTION ITEM REFERRING SECTION
Engine oil – level, leakage Section 0B
Engine coolant – level, leakage Section 0B
Fuel – level, leakage Section 0B
A/T fluid – level, leakage Section 0B
Air cleaner element – dirt, clogging Section 0B
Battery – fluid level, corrosion of terminal
Water pump belt – tension, damage Section 0B
Throttle cable – play, installation
Section 6E Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend
Connectors of electric wire harness – disconnection, friction
Fuses – burning Section 8
Parts – installation, bolt – looseness
Parts – deformation
Other parts that can be checked visually
Also check following items at engine start, if possible
Malfunction indicator lamp – operation Section 6
Charge warning lamp – operation Section 6H
Engine oil pressure warning lamp – operation Section 8 (Section 6 for pressure check)
Engine coolant temp. meter – operation Section 8
Fuel level meter – operation Section 8
Tachometer, if equipped – operation
Abnormal air being inhaled from air intake system
Exhaust system – leakage of exhaust gas, noise
Other parts that can be checked visually

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[D] Fig. 4 for Step 7 or 8 / [E] Fig. 5 for Step 10 / [F] Fig. 6 for Step 13
Engine diagnosis table
Perform troubleshooting referring to following table when ECM has no DTC and no abnormality found in visual
inspection and engine basic inspection previously.
Condition Possible Cause Reference Item
Hard Starting
(Engine cranks OK)Faulty ignition coil Ignition coil assembly in Section 6F.
Faulty CMP sensing rotor or CKP sensing
rotorCMP sensing rotor or CKP sensing
rotor inspection in Section 6E.
Faulty idle air control system Diagnostic Flow Table B-4
Faulty ECT sensor, TP sensor, CKP sen-
sor, CMP sensor or MAP sensorECT sensor, TP sensor, CKP sensor,
CMP sensor or MAP sensor in Sec-
tion 6E.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty fuel injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning PCV system PCV system in Section 6E.
Low compression Compression check in Section 6A1.
Improper valve lash Valve lash in Section 6A1.
Improper valve timing Timing chain and chain tensioner in
Section 6A1.
Compression leak from valve seat Valves and cylinder head in Section
6A1.
Sticky valve stem Valves and cylinder head in Section
6A1.
Weak or damaged valve springs Valves and cylinder head in Section
6A1.
Compression leak at cylinder head gasket Valves and cylinder head in Section
6A1.
Sticking or damaged piston ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston, ring or cylinder Pistons, piston rings, connecting rods
and cylinders in Section 6A1.

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Excessive detonation
(The engine makes
sharp metallic knocks
that change with throt-
tle opening.
Sounds like pop corn
popping.)Engine overheating Refer to “Overheating” of this table.
Faulty spark plug Spark plugs in Section 6F.
Clogged fuel filter and fuel lines Diagnostic Flow Table B-3
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Poor performance of knock sensor, ECT
sensor or MAP sensorKnock sensor in this section, ECT
sensor or MAP sensor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Excessive combustion chamber deposits Piston and cylinder head in Section
6A1.
Overheating
Inoperative thermostat Thermostat in Section 6B.
Faulty A/C condenser fan motor or its cir-
cuitA/C condenser fan control system
check in Section 6E.
Loose or slip water pump belt ITEM1-1 Drive belt inspection and
change in Section 0B.
Poor water pump performance Water pump in Section 6B.
Clogged or leaky radiator Radiator in Section 6B.
Improper engine oil grade ITEM1-3 Engine oil and oil filter
change in Section 0B.
Clogged oil filter or oil strainer Oil pressure check in Section 6A1.
Poor oil pump performance Oil pressure check in Section 6A1.
Dragging brakes Diagnosis Table in Section 5.
Slipping clutch Diagnosis Table in Section 7C.
Blown cylinder head gasket Valves and cylinder head in Section
6A1.
Poor gasoline mileage
Faulty ignition coil Ignition coil assembly in Section 6F.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
High idle speed Refer to item “Improper Engine Idle
Speed” previously outlined.
Low compression Previously outlined.
Poor valve seating Valves and cylinder head in Section
6A1.
Dragging brakes Diagnosis Table in Section 5.
Slipping clutch Diagnosis Table in Section 7C.
Thermostat out of order Thermostat in Section 6B.
Improper tire pressure Refer to Section 3F. Condition Possible Cause Reference Item

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DTC P0136 Heated Oxygen Sensor (HO2S) Circuit Malfunction (Sensor-2)
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 158 °F or lower
–No exhaust gas leakage and loose connection
2) Warm up engine to normal operating temperature.
3) Drive vehicle under usual driving condition for 5 min. and check HO2S-2 output voltage and “short term fuel
trim” with “Data List” mode on scan tool, and write it down.
4) Stop vehicle (don’t turn ignition switch OFF).
5) Increase vehicle speed to higher than 20 mph, 32 km/h and then stop vehicle.
1. Heated oxygen sensor-2 (HO2S-2) [A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
DTC DETECTING CONDITION POSSIBLE CAUSE
Engine is warmed up and HO2S-2 voltage is 4.5 V or more.
(circuit open)
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 driving.Exhaust gas leakage
“W” or “B/Bl” circuit open or short
Heated oxygen sensor-2 malfunction
Fuel system malfunction
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.

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6) Repeat above steps 5) 4 times.
7) Increase vehicle speed to about 50 mph (80 km/h) in 3rd gear or 2 range.
8) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for
10sec. or more.
9) Stop vehicle (don’t turn ignition switch OFF) and run engine at idle for 2 min. After this step 9), if “Oxygen
Sensor Monitoring TEST COMPLETED” is displayed in “READINESS TESTS” mode and DTC is not dis-
played in “DTC” mode, confirmation test is completed.
If “TEST NOT COMPLTD” is still being displayed, proceed to next step 10).
10) Drive vehicle under usual driving condition for 10 min. (or vehicle is at a stop and run engine at idle for 10
min. or longer)
11) Stop vehicle (don’t turn ignition switch OFF). Confirm test results according to “Test Result Confirmation
Flow Table” in “DTC CONFIRMATION PROCEDURE” of DTC P0420.
INSPECTION
*Usual driving : Driving at 30 – 40 mph, 50 – 60 km/h including short stop according to traffic signal. (under driving condition other than high-load, high-engine
speed, rapid accelerating and decelerating)
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check exhaust system for leakage, loose con-
nection and damage.
Is it good condition?Go to Step 3. Repair or replace.
3 Check HO2S-2 and Its Circuit.
Was HO2S-2 output voltage indicated on scan
tool in step 3) of DTC confirmation test less
than 1.275 V?Go to Step 4.“B/Bl” or “W” circuit open
or HO2S-2 malfunction.
4 Check Short Term Fuel Trim.
Did short term fuel trim very within –20 – + 20%
range in step 3) of DTC confirmation test?Check “W” and “B/Bl” wire
for open and short, and
connection for poor con-
nection. If wire and con-
nection are OK, replace
HO2S-2.Check fuel system. Go to
DTC P0171 / P0172 Diag.
Flow Table.

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DTC P0171 Fuel System Too Lean
DTC P0172 Fuel System Too Rich
CIRCUIT DESCRIPTION
[a] : Signal to decrease amount of fuel injection [d] : A/F mixture becomes richer
(Oxygen concentration decreases)1. Injector
[b] : Signal to increase amount of fuel injection [e] : High voltage 2. Heated oxygen sensor-1 (HO2S-1)
[c] : A/F mixture becomes leaner
(Oxygen concentration increases)[f] : Low voltage
DTC DETECTING CONDITION POSSIBLE CAUSE
When following condition occurs while engine running
under closed loop condition.
–Air / fuel ratio too lean
(Total fuel trim (short and long terms added) is more
than 30%)
or
–Air / fuel ratio too rich
(Total fuel trim is less than –30%)
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring.Vacuum leaks (air drawn in).
Exhaust gas leakage.
Heated oxygen sensor-1 circuit malfunction.
Fuel pressure out of specification.
Fuel injector malfunction (clogged or leakage).
MAP sensor poor performance.
ECT sensor poor performance.
IAT sensor poor performance.
TP sensor poor performance.
EVAP control system malfunction.
PCV valve malfunction.

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5 Check Fuel Injectors and Circuit.
1) Using sound scope (4) or such, check operating
sound of each injector (5) when engine is run-
ning. Cycle of operating sound should vary
according to engine speed. See Fig. 3.
If no sound or an unusual sound is heard, check
injector circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel
injector connector.
3) Check for proper connection to fuel injector at
each terminal.
4) If OK, then check injector resistance.
See Fig. 4.
Injector resistance
11.3 – 13.8 ohm at 20 °C (68 °F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume
referring to Section 6E. See Fig. 5.
Injected fuel volume
43 – 47 cc/15 sec (1.45/1.51 – 1.58/1.65 US/
Imp.oz/15 sec)
7) Check each injector for fuel leakage after injec-
tor closed.
Fuel leakage
Less than 1 drop / min. (1)
Is check result in step 1) and 3) to 7) satisfactory?Go to Step 6. Check injector circuit or
replace fuel injector(s).
6 Check EVAP Canister Purge Valve.
1) Disconnect purge hose (2) from EVAP canister.
2) Place finger against the end of disconnected
hose.
3) Check that vacuum is not felt there when
engine is cool and running at idle. See Fig. 6.
Is vacuum felt?Check EVAP control
system (See Section
6E).Go to Step 7.
7 Check intake manifold absolute pressure sensor for
performance (See step 4) of DTC P0105 (No.11)
Diag. Flow Table).
Is it in good condition?Go to Step 8. Repair or replace.
8 Check engine coolant temp. sensor for perfor-
mance (See Section 6E).
Is it in good condition?Go to Step 9. Replace engine coolant
temp. sensor.
9 Check intake air temp. sensor for performance
(See Section 6E).
Is it in good condition?Go to Step 10. Replace intake air temp.
sensor.
10 Check throttle position sensor for performance
(See step 5) of DTC P0121 Diag. Flow Table).
Is it in good condition?Go to Step 11. Replace throttle position
sensor.
11 Check PCV valve for valve clogging
(See Section 6E).
Is it good condition?Substitute a known-
good ECM and recheck.Replace PCV valve. Step Action Yes No

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DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 158 °F or lower
–Engine coolant temp. : – 10 – 110 °C, 14 – 230 °F
4) Start engine and keep it at idle for 2 min. or more.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
6) If DTC is not detected at idle, consult usual driving based on information obtained in “Customer complaint
analysis” and “Freeze frame data check”.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
Engine under other than high revolution condition
Not on rough road
Engine speed changing rate (below specified value)
Manifold absolute pressure changing rate (below
specified value)
Throttle opening changing rate (below specified
value)
Misfire rate per 200 or 1000 engine revolutions (how
much and how often crankshaft revolution speed
changes) is higher than specified valueEngine overheating
Vacuum leaks (air inhaling) from air intake system
Ignition system malfunction (spark plug(s), high-
tension cord(s), ignition coil assembly)
Fuel pressure out of specification
Fuel injector malfunction (clogged or leakage)
Engine compression out of specification
Valve lash (clearance) out of specification
Manifold absolute pressure sensor malfunction
Engine coolant temp. sensor malfunction
PCV valve malfunction
EVAP control system malfunction
EGR system malfunction
NOTE:
Among different types of random misfire, if misfire occurs at cylinders 1 and 4 or cylinders 3 and 2
simultaneously, it may not possible to reconfirm DTC by using the following DTC confirmation proce-
dure. When diagnosing the trouble of DTC P0300 (Random misfire detected) of the engine which is
apparently misfiring, even if DTC P0300 cannot be reconfirmed by using the following DTC confirma-
tion procedure, proceed to the following Diag. Flow Table.
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine
Diag. Flow Table”.
2 Is there DTC other than Fuel system (DTC P0171/
P0172) and misfire (DTC P0300 – P0304)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.

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3 Check Ignition System.
1) Remove spark plugs and check them for;
Air gap : 1.0 – 1.1 mm (0.040 – 0.043 in.) See Fig. 1.
Carbon deposits / Insulator damage / Plug type
If abnormality is found, adjust, clean or replace by
referring to Section 6F. (See CAUTION)
2) Disconnect all injector connectors. See Fig. 2.
3) Connect spark plugs to high tension cords and then
ground spark plugs.
4) Crank engine and check that each spark plug sparks.
Are above check results satisfactory?Go to Step 4. Check ignition sys-
tem parts (Refer to
Section 6F).
4 Check Fuel Pressure (Refer to Section 6E for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig. 3.
3) Check fuel pressure.
Fuel pressure specification
With fuel pump operating and engine at stop :
270 – 310 kPa, 2.7 – 3.1 kg/cm
2, 38.4 – 44.0 psi.
At specified idle speed :
210 – 260 kPa, 2.1 – 2.6 kg/cm
2, 29.8 – 37.0 psi.
Is measured value as specified?Go to Step 5. Go to Diag. Flow
Table B-3 fuel pres-
sure check.
5 Check Fuel Injectors and Circuit.
1) sing sound scope (1) or such, check operating sound
of each injector (2) when engine is running. Cycle of
operating sound should very according to engine
speed. See Fig 4.
If no sound or an unusual sound is heard, check
injector circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel injec-
tor connector.
3) Check for proper connection to fuel injector at each
terminal.
4) If OK, then check injector resistance. See Fig. 5.
Injector resistance
11.3 – 13.8 ohm at 20 °C (68 °F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume referring
to Section 6E. See Fig. 6.
Injected fuel volume
43 – 47 cc/15 sec (1.45/1.51 – 1.58/1.65 US/Imp. oz/
15 sec)
7) Check each injector for fuel leakage after injector
closed.
Fuel leakage
Less than 1 drop/min.
Is check result in step 1) and 3) to 7) satisfactory?Go to Step 6. Check injector cir-
cuit or replace fuel
injector(s).
6 Check PCV valve for clogging (See Section 6E).
Is it in good condition?Go to Step 7. Replace PCV
valve. Step Action Yes No