2000 SUZUKI SWIFT engine overheat

6-1-24 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ConditionPossible CauseReferring Item
Overheating
Inoperative thermostat

Poor water pump performance

Clogged or leaky radiator

Improper engine oil grade

Clogged oil filter or oil strainer

Poor oil pump performance

Faulty radiator fan control system

Dragging brakes

Slipping clutch

Blown cylinder head gasketThermostat in Section 6B
Water pump in Section 6B
Radiator in Section 6B
Engine oil and oil filter change in
Section 0B
Oil pressure check in Section 6A1
Oil pressure check in Section 6A1
Radiator fan control system in
Section 6E2
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C
Cylinder head in Section 6A1
Poor gasoline
mileageIgnition system out of order

Leaks or loose connection of high-tension cord

Faulty spark plug (improper gap, heavy deposits
and burned electrodes, etc.)
Engine and emission control system out of
order

Malfunctioning EGR valve

High idle speed

Poor performance of TP sensor, ECT sensor or
MAP sensor

Faulty EGR valve

Faulty fuel injector(s)

Faulty ECM (PCM)
Low compression
Others

Poor valve seating

Dragging brakes

Slipping clutch

Thermostat out of order

Improper tire pressure
High-tension cords in Section 6F1
Spark plugs in Section 6F1
EGR system in Section 6E2
Refer to item “Improper engine
idle speed” previously outlined
TP sensor, ECT sensor or MAP
sensor in Section 6E2
EGR system in Section 6E2
Diagnostic Flow Table B-1
Previously outlined
Valves inspection in Section 6A1
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C
Thermostat in Section 6B
Refer to Section 3F
Excessive engine
oil consumptionOil leakage

Blown cylinder head gasket

Leaky camshaft oil seals
Oil entering combustion chamber

Sticky piston ring

Worn piston and cylinder

Worn piston ring groove and ring

Improper location of piston ring gap

Worn or damaged valve stem seal

Worn valve stem
Cylinder head in Section 6A1
Camshaft in Section 6A1
Piston cleaning in Section 6A1
Pistons and cylinders inspection
in Section 6A1
Pistons inspection in Section 6A1
Pistons assembly in Section 6A1
Valves removal and installation in
Section 6A1
Valves inspection in Section 6A1

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-25
ConditionPossible CauseReferring Item
Engine hesitates
(Momentary lack of
response as
accelerator is
depressed.
Can occur at all
vehicle speeds.
Usually most severe
when first trying to
make vehicle move,
as from a stop sign.)Ignition system out of order

Spark plug faulty or plug gap out of adjustment

Leaky high-tension cord
Fuel system out of order

Fuel pressure out of specification
Engine and emission control system out of
order

Malfunctioning EGR valve

Poor performance of TP sensor, ECT sensor or
MAP sensor

Faulty fuel injector

Faulty ECM (PCM)
Engine overheating
Low compression
Spark plugs in Section 6F1
High-tension cords in Section 6F1
Diagnostic Flow Table B-3
EGR system in section 6E2
TP sensor, ECT sensor or MAP
sensor in Section 6E2
Diagnostic Flow Table B-1
Refer to “Overheating” section
Previously outlined
Surge
(Engine power
variation under
steady throttle or
cruise.
Feels like vehicle
speeds up and down
with no change in
accelerator pedal.)Ignition system out of order

Leaky or loosely connected high-tension cord

Faulty spark plug (excess carbon deposits,
improper gap, and burned electrodes, etc.)
Fuel system out of order

Variable fuel pressure
–Kinky or damaged fuel hose and lines
–Faulty fuel pump (clogged fuel filter)
Engine and emission control system out of
order

Malfunctioning EGR valve

Poor performance of MAP sensor

Faulty fuel injector

Faulty ECM (PCM)
High-tension cords in Section 6F1
Spark plugs in Section 6F1
Diagnostic Flow Table B-3
EGR system in Section 6E2
MAP sensor in Section 6E2
Diagnostic Flow Table B-1
Excessive
detonation
(Engine makes
continuously
sharp metallic
knocks that change
with throttle opening.
Sounds like pop corn
popping.)Engine overheating
Ignition system out of order

Faulty spark plug

Loose connection of high-tension cord
Fuel system out of order

Clogged fuel filter (faulty fuel pump) or fuel lines

Air inhaling from intake manifold or throttle body
gasket
Engine and emission control system out of
order

Malfunctioning EGR valve

Poor performance of ECT sensor or MAP sensor

Faulty fuel injector(s).

Faulty ECM (PCM)

Excessive combustion chamber depositsRefer to “Overheating” section
Spark plugs in Section 6F1
High-tension cords in Section 6F1
Diagnostic Flow Table B-1 or B-2
EGR system in Section 6E2
ECT sensor or MAP sensor in
Section 6E2
Diagnostic Flow Table B-1
Piston and cylinder head cleaning
in Section 6A1

6-1-26 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ConditionPossible CauseReferring Item
Engine has no
powerIgnition system out of order

Faulty spark plug

Faulty ignition coil with ignitor

Leaks, loose connection or disconnection of
high-tension cord
Engine overheating
Fuel system out of order

Clogged fuel hose or pipe

Malfunctioning fuel pump

Air inhaling from intake manifold gasket or
throttle body gasket
Engine and emission control system out of
order

Malfunctioning EGR valve

Maladjusted accelerator cable play

Poor performance of TP sensor, ECT sensor or
MAP sensor

Faulty fuel injector(s)

Faulty ECM (PCM)
Low compression
Others

Dragging brakes

Slipping clutch
Spark plugs in Section 6F1
Ignition coil in Section 6F1
High-tension cords in Section 6F1
Refer to “Overheating” section
Diagnostic Flow Table B-3
Diagnostic Flow Table B-2
EGR system inspection in Section
6E2
Accelerator cable play in Section
6E2
TP sensor, ECT sensor or MAP
sensor in Section 6E2
Diagnostic Flow Table B-1
Previously outlined
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-27
ConditionPossible CauseReferring Item
Improper engine
idling or engine
fails to idleIgnition system out of order

Faulty spark plug

Leaky or disconnected high-tension cord

Faulty ignition coil with ignitor
Fuel system out of order

Fuel pressure out of specification

Leaky manifold, throttle body, or cylinder head
gasket
Engine and emission control system out of
order

Malfunctioning EGR valve

Faulty idle air control system

Faulty evaporative emission control system

Faulty EGR system

Faulty fuel injector(s)

Poor performance of ECT sensor, TP sensor or
MAP sensor

Faulty ECM (PCM)
Engine overheating
Low compression
Others

Loose connection or disconnection of vacuum
hoses

Malfunctioning PCV valve
Spark plugs in Section 6F
High-tension cords in Section 6F
Ignition coil in Section 6F
Diagnostic Flow Table B-3
EGR system in Section 6E2
Diagnostic Flow Table B-4
EVAP control system in Section
6E2
EGR system in Section 6E2
Diagnostic Flow Table B-1
ECT sensor, TP sensor or MAP
sensor in Section 6E2
Refer to “Overheating” section
Previously outlined
PCV system in Section 6E2

6-1-48 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
To combination
(ECT) meterTo other sensors
NOTE:
Before inspecting, be sure to check that cool-
ant temp. meter in combination meter indi-
cates normal operating temperature (Engine
is not overheating).
DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

Low engine coolant temperature (High voltage-High resistance)

High engine coolant temperature (Low voltage-Low resistance)
“Lg / R” circuit open or shorted to power

“G” circuit open

ECT sensor malfunction

ECM (PCM) malfunction
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 (SFI FOR G13) 6-1-69
Ignition coil assembly
for No.1 & No.4 spark plugs
Ignition coil assembly
for No.2 & No.3 spark plugs
Ignition switch
Main relay
Main
fuseRelay box
To ignition switch
CKP sensorCMP sensorNo.1 injector
No.2 injector
No.3 injector
No.4 injector Fuse box
DTC P0300 RANDOM MISFIRE DETECTED (Misfire detected at 2 or more
cylinders)
DTC P0301 CYLINDER 1 MISFIRE DETECTED
DTC P0302 CYLINDER 2 MISFIRE DETECTED
DTC P0303 CYLINDER 3 MISFIRE DETECTED
DTC P0304 CYLINDER 4 MISFIRE DETECTED
CIRCUIT DESCRIPTION
ECM (PCM) monitors crankshaft revolution speed and engine speed via the crankshaft position sensor and cylin-
der No. via the camshaft position sensor. Then it calculates the change in the crankshaft revolution speed and from
how many times such change occurred in every 200 or 1000 engine revolutions, it detects occurrence of misfire.
When ECM (PCM) detects a misfire (misfire rate per 200 revolutions) which can cause overheat and damage to
the three way catalytic converter, it makes the malfunction indicator lamp (MIL) flash as long as misfire occurs at
that rate.
After that, however, when the misfire rate drops, MIL remains ON until it has been judged as normal 3 times under
the same driving conditions.
Also, when ECM (PCM) detects a misfire (misfire rate per 1000 revolutions) which will not cause damage to three
way catalytic converter but can cause exhaust emission to be deteriorated, it makes MIL light according to the 2
driving cycle detection logic.

Below
specified value
6-1-70 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
1. CKP sensor signal
2. No.1 fuel injector signal
3. No.3 fuel injector signal
4. Fuel injection time
Display of fuel injection signal using oscilloscope
Waveforms at specified idle speed5ms/Div
DTC DETECTING CONDITIONPOSSIBLE CAUSE

Engine under other than high revolution condition

Not on rough road

Engine speed changing rate

Manifold absolute
pressure changing rate

Throttle opening changing rate

Misfire rate per 200 or 1000 engine revolutions (how
much and how often crankshaft revolution speed
changes) is higher than specified value
Engine 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
DTC CONFIRMATION PROCEDURE
NOTE:
Among different types of random misfire, if misfire occurs at cylinders 1 and 4 or cylinders 3 and 2 simulta-
neously, it may not possible to reconfirm DTC by using the following DTC confirmation procedure. When
diagnosing the trouble of DTC P0300 (Random misfire detected) of the engine which is apparently misfir-
ing, even if DTC P0300 cannot be reconfirmed by using the following DTC confirmation procedure, pro-
ceed 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 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 a tester.
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)
–Intake air temp.: between –10C and 80C (14F and 176F)
–Engine coolant temp.: –10C, 14F or higher
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 analy-
sis” and “Freeze frame data check”.
Reference

6B-4 ENGINE COOLING
COOLANT (WATER) TEMP. GAUGE
The coolant temp. gauge is included in engine coolant temp. (ECT)
sensor (1). This gauge activates a temp. meter in the instrument
cluster.
DIAGNOSIS
ConditionPossible CauseCorrection
Engine overheatsLoose or broken water pump belt
Not enough coolant
Faulty thermostat
Faulty water pump
Dirty or bent radiator fins
Coolant leakage on cooling system
Defective cooling fan motor
Plugged radiator
Faulty radiator cap
Maladjusted ignition timing
Dragging brakes
Slipping clutchAdjust or replace.
Check coolant level and add as
necessary.
Replace.
Replace.
Clean or remedy.
Repair.
Check and replace as
necessary.
Check and replace radiator as
necessary.
Replace.
Adjust.
Adjust brake.
Adjust or replace.