2001 SUZUKI GRAND VITARA gas

6-1-4 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
When disconnecting couplers, don’t pull wire harness but
make sure to hold coupler itself. With lock type coupler, be
sure to unlock before disconnection. Attempt to disconnect
coupler without unlocking may result in damage to coupler.
When connecting lock type coupler, insert it till clicking
sound is heard and connect it securely.
Precaution on Fuel System Service
Work must be done with no smoking, in a well-ventilated area and away from any open flames.
As fuel feed line (between fuel pump and fuel pressure regulator) is still under high fuel pressure even after
engine was stopped, loosening or disconnecting fuel feed line directly may cause dangerous spout of fuel to
occur where loosened or disconnected. Before loosening or disconnecting fuel feed line, make sure to
release fuel pressure according to “FUEL PRESSURE RELIEF PROCEDURE” in this section.
A small amount of fuel may be released after the fuel line is disconnected.
In order to reduce the chance of personal injury, cover the fitting to be disconnected with a shop cloth. Put
that cloth in an approved container when disconnection is completed.
Never run engine with fuel pump relay disconnected when engine and exhaust system are hot.
Fuel or fuel vapor hose connection varies with each type of
pipe. When reconnecting fuel or fuel vapor hose, be sure to
connect and clamp each hose correctly referring to left fig-
ure.
After connecting, make sure that the hose has no twist or
kink.
When installing fuel union bolt gasket, always use new gas-
ket and tighten union bolt to specified torque according to
“TIGHTENING TORQUE SPECIFICATION” in Section 6C.
When installing injector, fuel feed pipe or fuel pressure regu-
lator, lubricate its O-ring with gasoline.
When connecting fuel pipe flare nut, first tighten flare nut by
hand and then tighten it to specified torque.
[A] : With short pipe, fit hose as far as it reaches pipe joint as shown.
[B] : With following type pipe, fit hose as far as its peripheral projection as shown.
[C] : With bent pipe, fit hose as far as its bent part as shown or till pipe is about 20
to 30 mm (0.79 – 1.18 in.) into the hose.
[D] : With straight pipe, fit hose till pipe is about 20 to 30 mm (0.79 – 1.18 in.) into
the hose.
1. Hose
2. Pipe
3. Clamp
“a” : Clamp securely at a position 3 to 7 mm (0.12 – 0.27 in.) from hose end.
“b” : 20 to 30 mm (0.79 – 1.18 in.)

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-13
STEP 2. DIAGNOSTIC TROUBLE CODE (DTC)/FREEZE FRAME DATA CHECK
First, check DTC, referring to “DIAGNOSTIC TROUBLE CODE CHECK” in this section. If DTC is indicated,
record DTC and freeze frame data.
After that clear DTC referring to “DIAGNOSTIC TROUBLE CODE CLEARANCE” in this section. DTC indicates
malfunction that occurred in the system but does not indicate whether it exists now or it occurred in the past and
the normal condition has been restored now. To check which case applies, check the symptom in question
according to Step 5 and recheck DTC according to Step 6, 7.
Attempt to diagnose a trouble based on DTC in this step only or failure to clear the DTC (including pending DTC)
in this step will lead to incorrect diagnosis, trouble diagnosis of a normal circuit or difficulty in troubleshooting.
STEP 3. and 4. VISUAL INSPECTION
Be sure to perform visual check of the following items that support proper function of the engine.
STEP 5. TROUBLE SYMPTOM CONFIRMATION
Based on information obtained in Step 1 “CUSTOMER COMPLAINT ANALYSIS” and Step 2 “DTC/FREEZE
FRAME DATA CHECK”, confirm trouble symptoms. Also, reconfirm DTC according to “DTC CONFIRMATION
PROCEDURE” described in each “DTC FLOW TABLE”.NOTE:
For A/T vehicle, if only DTC P0705, P0715, P0720, P0741, P0743, P0751, P0753, P0756, P0758, or P1875
is indicated in this step, proceed to “DIAGNOSIS” in SECTION 7B1.
INSPECTION ITEM REFERRING SECTION
• Engine oil - - - - - level, leakage
• Engine coolant - - - - - level, leakage
• Fuel - - - - - level, leakage
• A/T fluid - - - - - level, leakage
• Air cleaner element - - - - - dirt, clogging
• Battery - - - - - fluid level, corrosion of terminal
• Water pump belt and/or cooling fan belt - - - - - tension, damage
• Accelerator cable - - - - - play, installation
• A/T throttle cable - - - - - play, installation
• Vacuum hoses of air intake system
- - - - - disconnection, looseness, deterioration, bend
• Connectors of electric wire harness - - - - - disconnection, friction
• Fuses - - - - - burning
• 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
– Charge warning lamp - - - - - operation
– Engine oil pressure warning lamp - - - - - operation
– Engine coolant temp. meter - - - - - operation
– Fuel lever meter - - - - - operation
– Abnormal air being inhaled from air intake system
– Exhaust system - - - - - leakage of exhaust gas, noise
– Other parts that can be checked visuallySECTION 0B
SECTION 0B
SECTION 0B
SECTION 0B
SECTION 0B
SECTION 0B
SECTION 6C
SECTION 6E2
SECTION 6E2
SECTION 6A2
SECTION 8
SECTION 6-1
SECTION 6H
SECTION 8/6A2
SECTION 8
SECTION 8

6-1-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
P0174 Fuel system too lean (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is larger
than specification for specified time or
longer. (Fuel trim toward rich side is
large.)2 driving
cyclesNot
applicable
P0175 Fuel system too rich (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is
smaller than specification for specified
time or longer. (Fuel trim toward lean
side is large.)2 driving
cyclesNot
applicable
P0300
P0301
P0302
P0303
P0304
P0305
P0306Random misfire detected
Cylinder 1 misfire detected
Cylinder 2 misfire detected
Cylinder 3 misfire detected
Cylinder 4 misfire detected
Cylinder 5 misfire detected
Cylinder 6 misfire detectedMisfire of such level as to cause dam-
age to three way catalystMIL flashing
during mis-
fire detec-
tionNot
applicable
Misfire of such level as to deteriorate
emission but not to cause damage to
three way catalyst2 driving
cyclesNot
applicable
P0325
(No.43)Knock sensor circuit malfunc-
tionSensor output too low
1 driving
cycle1 driving
cycle
Sensor output too high
P0335Crankshaft position sensor cir-
cuit malfunctionNo signal during engine running and
CMP sensor signal inputting1 driving
cycleNot
applicable
P0340
(No.42)Camshaft position sensor cir-
cuit malfunctionNo signal for 3 sec. during engine
cranking, REF signal pattern incor-
rect or POS signal voltage too high or
too low1 driving
cycleNot
applicable
P0400Exhaust gas recirculation flow
malfunction detectedExcessive or insufficient EGR flow.2 driving
cyclesNot
applicable
P0403
(No.51)EGR valve circuit malfunctionEGR valve electrical circuit open or
shot to ground1 driving
cycle1 driving
cycle
P0420Catalyst system efficiency
below threshold (Bank 1)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0430Catalyst system efficiency
below threshold (Bank 2)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0443Purge control valve circuit
malfunctionPurge control valve circuit is open or
shorted to ground.2 driving
cyclesNot
applicable
P0500
(No.24)Vehicle speed sensor mal-
functionNo signal while running in “D” range
or during fuel cut at decelerating.2 driving
cycles1 driving
cycle DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-31
Engine Diagnosis Table
Perform troubleshooting referring to following table when ECM (PCM) has detected no DTC and no abnormality
has been found in visual inspection and engine basic inspection previously.
Condition Possible Cause Correction
Hard starting
(Engine cranks OK)Faulty idle air control system “DIAG. FLOW TABLE B-4” in this
section.
Faulty ECT sensor or MAF sensor ECT sensor or MAF sensor in Sec-
tion 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Compression check in Section
6A2.
Faulty hydraulic valve lash adjuster Valve lash adjuster in Section 6A2.
Compression leak from valve seat Valves inspection in Section 6A2.
Sticky valve stem Valves inspection in Section 6A2.
Weak or damaged valve springs Valves spring inspection in Section
6A2.
Compression leak at cylinder head gasket Cylinder head inspection in Section
6A2.
Sticking or damaged piston ring Piston ring inspection in Section
6A2.
Worn piston, ring or cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Malfunctioning PCV valve PCV system inspection in Section
6E2.
Engine has no power
Engine overheating Refer to “OVERHEATING” in this
table.
Defective spark plug Spark plugs in Section 6F2.
Faulty ignition coil with ignitor Ignition coil in Section 6F2.
Fuel pressure out of specification
(dirty fuel filter, dirty or clogged fuel hose or
pipe, malfunctioning fuel pressure regulator,
malfunctioning fuel pump)“DIAG. FLOW TABLE B-3” in this
section.
Maladjusted TP sensor installation angle TP sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector in Section 6E2.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Refer to the same item in “HARD
STARTING” of this table.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-33
Surges
(Engine power varia-
tion under steady
throttle or cruise.
Feels like the vehicle
speeds up and down
with no change in the
accelerator pedal.)Defective spark plug
(excess carbon deposits, improper gap, and
burned electrodes, etc.)Spark plugs in Section 6F2.
Variable fuel pressure
(clogged fuel filter, kinky or damaged fuel hose
and line, faulty fuel pressure regulator)“DIAG. FLOW TABLE B-3” in this
section.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty MAF sensor MAF sensor in Section 6E2.
Faulty injector Fuel injector in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Excessive detonation
(The engine makes
sharp metallic knocks
that change with throt-
tle opening. Sounds
like pop corn pop-
ping.)Engine overheating Refer to “OVERHEATING” in this
table.
Faulty spark plug Spark plugs in Section 6F2.
Improper ignition timing Ignition timing in Section 6F2.
Clogged fuel filter and fuel lines Fuel pressure check in Section
6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty ECT sensor or MAF sensor ECT sensor or MAF sensor in Sec-
tion 6E2.
Faulty injector Fuel injector in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Excessive carbon deposits in combustion
chamberPiston and cylinder head cleaning
in Section 6A2.
Poor knock sensor performance “DTC P0325 DIAG. FLOW TABLE”
in this section.
Overheating
Inoperative thermostat Thermostat in Section 6B.
Poor water pump performance Water pump in Section 6B.
Clogged or leaky radiator Radiator in Section 6B.
Improper engine oil grade Engine oil and oil filter change in
Section 0B.
Clogged oil filter or oil strainer Oil pressure check in Section 6A2.
Poor oil pump performance Oil pressure check in Section 6A2.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
Blown cylinder head gasket Cylinder head inspection in Section
6A2. Condition Possible Cause Correction

6-1-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Poor gasoline mileage
Faulty spark plug (improper gap, heavy depos-
its, and burned electrodes, etc.)Spark plugs in Section 6F2.
Fuel pressure out of specification “DIAG. FLOW TABLE B-3” in this
section.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Refer to the same item in “HARD
STARTING” of this table.
Poor valve seating Valves inspection in Section 6A2.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
Thermostat out of order Thermostat in Section 6B.
Improper tire pressure Diagnosis in Section 3.
Excessive engine oil
consumptionSticky piston ring Piston cleaning in Section 6A2.
Worn piston and cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Worn piston ring groove and ring Pistons and piston rings inspection
in Section 6A2.
Improper location of piston ring gap Pistons installation in Section 6A2.
Worn or damaged valve stem seal Valves and cylinder head in Sec-
tion 6A2.
Worn valve stem Valves inspection in Section 6A2.
Low oil pressure
Improper oil viscosity Engine oil and oil filter change in
Section 0B.
Malfunctioning oil pressure switch Oil pressure switch inspection in
Section 8.
Clogged oil strainer Oil pan and oil pump strainer clean-
ing in Section 6A2.
Functional deterioration of oil pump Oil pump in Section 6A2.
Worn oil pump relief valve Oil pump in Section 6A2.
Excessive clearance in various sliding parts “INSPECTION” for each parts in
Section 6A2. Condition Possible Cause Correction

6-1-76 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0171/P0172 Fuel System Too Lean/Rich (Bank 1)
DTC DETECTING CONDITION AND POSSIBLE CAUSE
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and warm up
engine completely.
3) Increase vehicle speed to 50 – 60 km/h (30 – 40 mph).
4) Keep driving above vehicle speed for 3 min. or more.
5) Stop vehicle and check pending DTC by using scan tool.DTC DETECTING CONDITION TROUBLE AREA
When running after engine warmed (2 driving cycle
detection logic).
• Short term fuel trim exceeding 15 % or long term fuel
trim exceeding 20 % and total trim exceeding 43 % is
detected.
– Fuel system too lean
• Short term fuel trim less than – 11 % or long term fuel
trim less than – 11 % and total trim less than – 30 % is
detected.
– Fuel trim too rich• Vacuum leaks (air inhaling)
• Exhaust gas leakage
• Fuel pressure out of specification
• Heated oxygen sensor malfunction
• EGR system malfunction
• MAF sensor poor performance
• ECT sensor poor performance
• Fuel level sensor.
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.
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. at start : – 8 – 60°C (18 – 140°F)
Engine coolant temp. at start : – 8 – 95°C (18 – 203°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : 110°C (230°F) or lower

6-1-78 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0174/P0175 Fuel System Too Lean/Rich (Bank 2)
DTC DETECTING CONDITION AND POSSIBLE CAUSE
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and warm up
engine completely.
3) Increase vehicle speed to 50 – 60 km/h (30 – 40 mph).
4) Keep driving above vehicle speed for 3 min. or more.
5) Stop vehicle and check pending DTC by using scan tool.DTC DETECTING CONDITION TROUBLE AREA
When running after engine warmed (2 driving cycle
detection logic).
• Short term fuel trim exceeding 15 % or long term fuel
trim exceeding 20 % and total trim exceeding 43 % is
detected.
– Fuel system too lean
• Short term fuel trim less than – 11 % or long term fuel
trim less than – 11 % and total trim less than – 30 % is
detected.
– Fuel trim too rich• Vacuum leaks (air inhaling)
• Exhaust gas leakage
• Fuel pressure out of specification
• Heated oxygen sensor malfunction
• EGR system malfunction
• MAF sensor poor performance
• ECT sensor poor performance
• Fuel level sensor.
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.
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. at start : – 8 – 60°C (18 – 140°F)
Engine coolant temp. at start : – 8 – 95°C (18 – 203°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : 110°C (230°F) or lower