Engine Diagnosis Table - Suzuki GRAND VITARA XL-7 Owner's Manual

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