Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 26

1A-51 Engine General Information and Diagnosis: For Petrol Engine Model

13 Check fuel injector for operation

1) Install spark plugs and connect injector connectors.
2) Using sound scope (1), check operating sound of each 

injector (2) when cranking engine.

Was injector operating sound heard from all injectors?

Go to “Engine Symptom 
Diagnosis: For Petrol 
Engine Model”.

Go to “Fuel Injector 
Circuit Check: For 
Petrol Engine Model”.

Step

Action

Yes

No

I3RM0A110015-01

Engine General Information and Diagnosis: For Petrol Engine Model 1A-52

Engine Symptom Diagnosis

S6JB0A1114010

Perform troubleshooting referring to the followings when ECM has detected no DTC and no abnormality has been 
found in “Visual Inspection: For Petrol Engine Model” and “Engine Basic Inspection: For Petrol Engine Model”.

Condition

Possible cause

Correction / Reference Item

Hard starting (Engine 
cranks OK)

Faulty spark plug

“Spark Plug Inspection: For Petrol Engine 
Model in Section 1H”

Leaky high-tension cord (for M16 
engine)

“High-Tension Cord Inspection (For M16 
Engine): For Petrol Engine Model in Section 
1H”

Loose connection or disconnection of 
high-tension cord(s) or lead wire(s) (for 
M16 engine)

“High-Tension Cord Removal and Installation 
(For M16 Engine): For Petrol Engine Model in 
Section 1H”

Faulty ignition coil

“Ignition Coil Assembly (Including ignitor) 
Inspection: For Petrol Engine Model in Section 
1H”

Dirty or clogged fuel hose or pipe

“Fuel Pressure Check: For Petrol Engine 
Model”

Malfunctioning fuel pump

“Fuel Pressure Check: For Petrol Engine 
Model”

Air drawn in through intake manifold 
gasket or throttle body gasket
Faulty electric throttle body assembly

“Electric Throttle Body Assembly On-Vehicle 
Inspection: For Petrol Engine Model in Section 
1C”

Faulty accelerator pedal position (APP) 
sensor assembly

“Accelerator Pedal Position (APP) Sensor 
Assembly Inspection: For Petrol Engine Model 
in Section 1C”

Faulty ECT sensor or MAF sensor

“Engine Coolant Temperature (ECT) Sensor 
Inspection: For Petrol Engine Model in Section 
1C” or “Mass Air Flow (MAF) and Intake Air 
Temperature (IAT) Sensor Inspection: For 
Petrol Engine Model in Section 1C”

Faulty ECM
Low compression

“Compression Check: For M16A Engine with 
VVT in Section 1D” or “Compression Check: 
For J20 Engine in Section 1D”

Poor spark plug tightening or faulty 
gasket

“Spark Plug Removal and Installation: For 
Petrol Engine Model in Section 1H”

Compression leak from valve seat

“Valves and Valve Guides Inspection: For J20 
Engine in Section 1D” or “Valves and Valve 
Guides Inspection: For M16A Engine with VVT 
in Section 1D”.

1A-53 Engine General Information and Diagnosis: For Petrol Engine Model

Hard starting (Engine 
cranks OK)

Sticky valve stem

“Valves and Valve Guides Inspection: For J20 
Engine in Section 1D” or “Valves and Valve 
Guides Inspection: For M16A Engine with VVT 
in Section 1D”.

Weak or damaged valve springs

“Valve Spring Inspection: For J20 Engine in 
Section 1D” or “Valve Spring Inspection: For 
M16A Engine with VVT in Section 1D”

Compression leak at cylinder head 
gasket

“Cylinder Head Inspection: For J20 Engine in 
Section 1D” or “Cylinder Head Inspection: For 
M16A Engine with VVT in Section 1D”

Sticking or damaged piston ring

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Cylinders, Pistons 
and Piston Rings Inspection: For M16A Engine 
with VVT in Section 1D”

Worn piston, ring or cylinder

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Cylinders, Pistons 
and Piston Rings Inspection: For M16A Engine 
with VVT in Section 1D”

Malfunctioning PCV valve

“PCV Valve Inspection: For Petrol Engine 
Model in Section 1B”

Camshaft position control (VVT) system 
out of order (for M16 engine)

“Oil Control Valve Inspection: For M16A 
Engine with VVT in Section 1D”

Faulty EGR system

“EGR System Inspection: For Petrol Engine 
Model in Section 1B”

Low oil pressure

Improper oil viscosity

“Engine Oil and Filter Change (Petrol Engine 
Model) in Section 0B”

Malfunctioning oil pressure switch

“Oil Pressure Switch Inspection in Section 9C”

Clogged oil strainer

“Oil Pan and Oil Pump Strainer Cleaning: For 
J20 Engine in Section 1E” or “Oil Pan and Oil 
Pump Strainer Cleaning: For M16A Engine 
with VVT in Section 1E”

Functional deterioration of oil pump

“Oil Pump Inspection: For J20 Engine in 
Section 1E” or “Oil Pump Inspection: For M16A 
Engine with VVT in Section 1E”

Worn oil pump relief valve

“Oil Pump Inspection: For J20 Engine in 
Section 1E” or “Oil Pump Inspection: For M16A 
Engine with VVT in Section 1E”

Excessive clearance in various sliding 
parts

Engine noise – Valve 
noise

NOTE
Before checking 
mechanical noise, make 
sure that:
• Specified spark plug is 

used.

• Specified fuel is used.

 

Improper valve lash

“Camshaft, Tappet and Shim Inspection: For 
J20 Engine in Section 1D” or “Camshaft, 
Tappet and Shim Inspection: For M16A Engine 
with VVT in Section 1D”

Worn valve stem and guide

“Valves and Valve Guides Inspection: For J20 
Engine in Section 1D” or “Valves and Valve 
Guides Inspection: For M16A Engine with VVT 
in Section 1D”.

Weak or broken valve spring

“Valve Spring Inspection: For J20 Engine in 
Section 1D” or “Valve Spring Inspection: For 
M16A Engine with VVT in Section 1D”

Warped or bent valve

“Valves and Valve Guides Inspection: For J20 
Engine in Section 1D” or “Valves and Valve 
Guides Inspection: For M16A Engine with VVT 
in Section 1D”.

Condition

Possible cause

Correction / Reference Item

Engine General Information and Diagnosis: For Petrol Engine Model 1A-54

Engine noise – Piston, 
ring and cylinder noise

NOTE
Before checking 
mechanical noise, make 
sure that:
• Specified spark plug is 

used.

• Specified fuel is used.

 

Worn piston, ring and cylinder bore

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Cylinders, Pistons 
and Piston Rings Inspection: For M16A Engine 
with VVT in Section 1D”

Engine noise – 
Connecting rod noise

NOTE
Before checking 
mechanical noise, make 
sure that:
• Specified spark plug is 

used.

• Specified fuel is used.

 

Worn piston, ring and cylinder bore

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Cylinders, Pistons 
and Piston Rings Inspection: For M16A Engine 
with VVT in Section 1D”

Worn rod bearing

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Crank Pin and 
Connecting Rod Bearings Inspection: For 
M16A Engine with VVT in Section 1D”

Worn crank pin

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Inspection and Cleaning: For J20 
Engine in Section 1D” or “Crank Pin and 
Connecting Rod Bearings Inspection: For 
M16A Engine with VVT in Section 1D”

Loose connecting rod nuts

“Pistons, Piston Rings, Connecting Rods and 
Cylinders Removal and Installation: For J20 
Engine in Section 1D” or “Pistons, Piston 
Rings, Connecting Rods and Cylinders 
Removal and Installation: For M16A Engine 
with VVT in Section 1D”

Low oil pressure

Condition “Low oil pressure”

Engine noise – 
Crankshaft noise

NOTE
Before checking 
mechanical noise, make 
sure that:
• Specified spark plug is 

used.

• Specified fuel is used.

 

Low oil pressure

Condition “Low oil pressure”

Worn bearing

“Main Bearings, Crankshaft and Cylinder Block 
Inspection: For J20 Engine in Section 1D” or 
“Main Bearings Inspection: For M16A Engine 
with VVT in Section 1D”

Worn crankshaft journal

“Main Bearings, Crankshaft and Cylinder Block 
Inspection: For J20 Engine in Section 1D” or 
“Crankshaft Inspection: For M16A Engine with 
VVT in Section 1D”

Loose bearing cap bolts

“Main Bearings, Crankshaft and Cylinder Block 
Removal and Installation: For J20 Engine in 
Section 1D” or “Main Bearings, Crankshaft and 
Cylinder Block Removal and Installation: For 
M16A Engine with VVT in Section 1D”

Excessive crankshaft thrust play

“Main Bearings, Crankshaft and Cylinder Block 
Inspection: For J20 Engine in Section 1D” or 
“Crankshaft Inspection: For M16A Engine with 
VVT in Section 1D”

Condition

Possible cause

Correction / Reference Item