2000 SUZUKI SWIFT SF310 Service Workshop Manual

6-70 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE“.
2Is there DTC other than Fuel system (DTC P0171 / P0172)
and misfire (DTC P0300-P0303)?Go to applicable
DTC Diag.
Flow Table.Go to Step 3.
3Check 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.
2) Disconnect injector connector. 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
system parts
(Refer to Section
6F).
4Check Fuel Pressure (Refer to Section 6E1 for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig. 3.
3) Check fuel pressure.
With fuel pump operating
and engine at stop : 160 – 210 kPa, 1.6 – 2.1 kg / cm
2,
22.7 – 29.9 psi.
At specified idle speed : 90 – 140 kPa, 0.9 – 1.4 kg / cm
2,
12.8 – 20.0 psi.
Is measured value as specified?
Go to Step 5.Go to Diag. Flow
Table B-3 fuel
pressure check.
5Check Fuel Injector and Circuit.
1) Turn ignition switch OFF and disconnect fuel injector
connector.
2) Check for proper connection to fuel injector at each terminal.
3) If OK, then check injector resistance. See Fig. 4.
Injector resistance: 0.5 – 1.5 Ω at 20C (68F).
4) Connect injector connector.
5) Check that fuel is injected out in conical shape from fuel
injector when running engine.
6) Check injector for fuel leakage after engine stop.
Fuel leakage: Less than 1 drop / min.
Is check result satisfactory?Go to Step 6.Check injector
circuit or replace
fuel injector.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-71
1. Throttle body
2. Fuel feed hose
GoodNo good1. Injector connector
STEPACTIONYESNO
6Check PCV valve for clogging (See Section 6E1).
Is it in good condition?Go to Step 7.Replace PCV valve.
7Check EVAP Canister Purge Valve for Closing.
1) Disconnect purge hose (1) 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. 5.
Is vacuum felt?Check EVAP
control system
(See Section 6E1).Go to Step 8.
8Check intake manifold pressure sensor for performance
(See Section 6E1).
Is it in good condition?Go to Step 9.Repair or replace.
9Check engine coolant temp. sensor for performance
(See Section 6E1).
Is it in good condition?Go to Step 10.Replace engine
coolant temp.
sensor.
10Check parts or system which can cause engine rough
idle or poor performance.
–Engine compression (See Section 6A).
–Valve lash (See Section 6A).
–Valve timing (Timing belt installation. See Section 6A).
Are they in good condition?Check wire harness
and connection of
ECM (PCM) ground,
ignition system and
fuel injector for
intermittent open
and short.Repair or replace.
Fig. 1 for Step 3 Fig. 2 for Step 3 Fig. 3 for Step 4
Fig. 4 for Step 5 Fig. 5 for Step 7

Oscilloscope Waveforms
Crankshaft
timing belt pulleyCKP
sensor
2V/Div.
5ms/Div.
Waveforms at specified idle speed
6-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0335 CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

No CKP sensor signal during 1 revolution of
camshaft.
CKP sensor circuit open or short.

Crankshaft timing belt pulley teeth damaged.

CKP sensor malfunction, foreign material being
attached or improper installation.

ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-3 (+) and C01-11 (–) of ECM (PCM) connector connected to ECM
(PCM) and check CKP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-73
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check CKP Sensor for Resistance.
1) Disconnect CKP sensor connector with ignition
switch OFF.
2) Then check for proper connection to CKP sensor
at “W/B” and “W/R” wire terminals.
3) If OK, measure sensor resistance between
terminals. See Fig. 1.
CKP sensor resistance: 360 – 460 Ω
at 20C, (68F)
4) Measure resistance between each terminal and
ground.
Insulation resistance: 1 MΩ or more.
Were measured resistance valves in step 3) and 4)
as specified?Go to Step 3.Replace CKP sensor.
3Check visually CKP sensor and pulley for the
following. See Fig. 2.

Damage

No foreign material attached.

Correct installation.
Are they in good condition?“W/B” or “W/R” wire
open or shorted to
ground, or poor
connection at C01-3
or C01-11.
If wire and connection
are OK, intermittent
trouble or faulty ECM
(PCM).
Recheck for
intermittent referring
to “Intermittent and
Poor Connection” in
Section 0A.Clean, repair or
replace.
Fig. 1 for Step 2 Fig. 2 for Step 3

Display of fuel injection signal using oscilloscope
1. CMP sensor signal
2. Fuel injector signal
3. Fuel injection time
2V/Div.
20V/Div.1
2
10ms/Div
Waveforms at specified idle speed 3 Sensor rotor
in distributorCamshaft
position sensor
6-74 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0340 CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

No CMP sensor signal for 2 seconds at engine
cranking (CKP sensor signal is inputted).
CMP sensor circuit open or short.

Signal rotor teeth damaged.

CMP sensor malfunction, foreign material being
attached or improper installation.

ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-2 and C01-10 of ECM (PCM) connector connected to ECM (PCM)
and check CMP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC.
2) Start engine and keep it at idle for 1 min.
3) Select “DTC” mode on scan tool and check DTC.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-75
Fig. 1 for Step 3 Fig. 2 for Step 5
“a”: Air gap
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Is DTC P1500 (Engine starter signal circuit
malfunction) detected?Go to DTC P1500
Diag. Flow Table.Go to Step 3.
3Check CMP Sensor for Resistance.
1) Measure resistance of CMP sensor by referring to
“CMP SENSOR (PICK UP COIL) RESISTANCE”
in SECTION 6F.
Is resistance within specified value?Go to Step 4.Faulty CMP sensor.
4Check Wire Harness.
1) With ignition switch at OFF position, disconnect
ECM (PCM) electrical connectors.
2) Measure resistance from terminal “C01-2” to
“C01-10” of ECM (PCM) connector. See Fig. 1.
Is resistance within 185 – 275 Ω at 20C (68F)?Go to Step 5.“W” or “Or” wire open
or short.
Poor connection of
CMP sensor
connector terminal.
5Check Air Gap Between Rotor Tooth and Sensor. See
Fig. 2.
1) Remove Distributor cap.
2) Visually inspect CMP sensor signal rotor for
damage.
3) Measure air gap by referring “SIGNAL ROTOR
AIR GAP” in Section 6F.
Was any damage found?Faulty CMP sensor
signal rotor.Poor connection of
ECM (PCM)
connector terminal.
If OK, substitute a
known-good ECM
(PCM) and recheck
CMP.

6-76 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Oscilloscope Waveforms
Engine running at
Closed loop conditionFuel
CutIdle after fuel cut 0.5 V / Div
2 sec. / Div Heated
oxygen
sensor-1
Warm up three way
catalytic converter (if equipped)
Three way catalytic converterTo other sensor
To other
sensors
Heated oxygen sensor-2
G
DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD
CIRCUIT DESCRIPTION
ECM (PCM) monitors oxygen concentration in the exhaust gas which has passed the three way catalytic converter
by HO2S-2.
When the catalyst is functioning properly, the variation cycle of HO2S-2 output voltage (oxygen concentration) is
slower than that of HO2S-1 output voltage because of the amount of oxygen in the exhaust gas which has been
stored in the catalyst.
Reference
DTC DETECTING CONDITIONPOSSIBLE CAUSE

While vehicle running at constant speed under other
than high load.

Time from rich or lean switching command is output
till HO2S-2 output voltage crosses 0.45 V is less than
specified value.
2 driving cycle detection logic, monitoring once / 1
driving.
Exhaust gas leak

Three way catalytic converter malfunction

Fuel system malfunction

HO2S-2 malfunction

HO2S-1 malfunction

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-77
1) 2) 3) 4) 35 – 45 mph
(55 – 65 km / h)
30 – 40 mph
(50 – 60 km / h)
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and be very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 persons, a driver and tester, on a level road.
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.: –10C, 14F or higher
–Intake air temp.: 70C, 158F or lower
–Engine coolant temp.: 70 – 11 0C, 158 – 230F
2) Start engine and drive vehicle at 40 – 47 mph, 65 – 75 km / h for 15 min. or longer.
While this driving, if “Catalyst Monitoring TEST COMPLETED” is displayed in “READINESS TESTS” mode and
DTC is not displayed in “DTC” mode, confirmation test is completed.
If “TEST NOT COMPLTD” is still being displayed, continue test driving.
3) Decrease vehicle speed at 28 – 34 mph, 45 – 55 km / h, and hold throttle valve at that opening position for 2 min.
and confirm that short term fuel trim vary within –20% –+20% range.
4) Stop vehicle (do not turn ignition switch OFF) and confirm test results according to following “Test Result Con-
firmation Flow Table”.
Test Result Confirmation Flow Table
STEPACTIONYESNO
1Check DTC in “DTC” mode and pending DTC in
“ON BOARD TEST” or “PENDING DTC” mode.
Is DTC or pending DTC displayed?Proceed to applicable
DTC Diag. Flow Table.Go to Step 2.
2Set scan tool to “READINESS TESTS” mode and
check if testing has been completed.
Is test completed?No DTC is detected
(confirmation test is
completed).Repeat DTC
confirmation
procedure.