Suzuki GRAND VITARA Owner's Manual page 111

Condition
Excessive hydrocarbon
(HC) emission or carbon
monoxide (CO)
Excessive nitrogen
oxides (NOx) emission
Possible cause
Faulty spark plug
Leaky or disconnected high-tension cord
(for M16 engine)
Faulty ignition coil with ignitor
Low compression
Lead contamination of three way
catalytic converter
Faulty evaporative emission control
system
Fuel pressure out of specification
Closed loop system (A/F feedback
compensation) fails (Faulty TP sensor,
Poor performance of ECT sensor or
MAF sensor)
Faulty electric throttle body assembly
Faulty accelerator pedal position (APP)
sensor assembly
Faulty injector(s)
Faulty ECM
Engine not at normal operating
temperature
Clogged air cleaner
Vacuum leaks
Camshaft position control (VVT) system
out of order (for M16 engine)
Improper ignition timing
Lead contamination of catalytic
converter
Faulty EGR system
Fuel pressure out of specification
Closed loop system (A/F feedback
compensation) fails (Faulty TP sensor,
Poor performance of ECT sensor or
MAF sensor)
Faulty electric throttle body assembly
Faulty accelerator pedal position (APP)
sensor assembly
Faulty injector(s)
Faulty ECM
Camshaft position control (VVT) system
out of order (for M16 engine)
Engine General Information and Diagnosis:
Correction / Reference Item
"Spark Plug Inspection: in Section 1H"
"High-Tension Cord Removal and Installation
(For M16 Engine): in Section 1H"
"Ignition Coil Assembly (Including ignitor)
Inspection: in Section 1H"
"Compression Check: For J20 Engine in
Section 1D" or "Compression Check: For
M16A Engine with VVT in Section 1D"
Check for absence of filler neck restrictor.
"EVAP Canister Purge Inspection: in Section
1B"
"Fuel Pressure Check: "
"Electric Throttle Body Assembly On-Vehicle
Inspection: in Section 1C", "Engine Coolant
Temperature (ECT) Sensor Inspection: in
Section 1C" or "Mass Air Flow (MAF) and
Intake Air Temperature (IAT) Sensor
Inspection: in Section 1C"
"Electric Throttle Body Assembly On-Vehicle
Inspection: in Section 1C"
"Accelerator Pedal Position (APP) Sensor
Assembly Inspection: in Section 1C"
"Fuel Injector Circuit Check: "
"Air Cleaner Filter Inspection and Cleaning:
For J20 Engine in Section 1D" or "Air Cleaner
Filter Inspection and Cleaning: For M16A
Engine with VVT in Section 1D"
"Engine Vacuum Check: For J20 Engine in
Section 1D" or "Engine Vacuum Check: For
M16A Engine with VVT in Section 1D"
"Oil Control Valve Inspection: For M16A
Engine with VVT in Section 1D"
"Ignition Timing Inspection: in Section 1H"
Check for absence of filler neck restrictor.
"EGR System Inspection: in Section 1B"
"Fuel Pressure Check: "
"Electric Throttle Body Assembly On-Vehicle
Inspection: in Section 1C", "Engine Coolant
Temperature (ECT) Sensor Inspection: in
Section 1C" or "Mass Air Flow (MAF) and
Intake Air Temperature (IAT) Sensor
Inspection: in Section 1C"
"Electric Throttle Body Assembly On-Vehicle
Inspection: in Section 1C"
"Accelerator Pedal Position (APP) Sensor
Assembly Inspection: in Section 1C"
"Fuel Injector Circuit Check: "
"Oil Control Valve Inspection: For M16A
Engine with VVT in Section 1D"
1A-56