6-2-30 ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE)
Excessive hydrocar-
bon (HC) emission
or carbon monox-
ide (CO)
Faulty spark plug “Spark Plugs Inspection” in Section
6F2.
Leaky or disconnected high-tension cord “High-tension Cords Inspection” in Sec-
tion 6F2.
Faulty ignition coil with ignitor “Ignition Coil Assembly (Including Igni-
tor) Inspection” in Section 6F2.
Low compression “Compression Check” in Section 6A2.
Lead contamination of three way catalytic
converter
Check for absence of filler neck restric-
tor.
Faulty evaporative emission control system “Evaporative Emission Control System
Inspection” in Section 6E2.
Fuel pressure out of specification “Table B-3 Fuel Pressure Check” in this
section.
Closed loop system (A/F feed back compen-
sation) fails
• Faulty TP sensor “TP Sensor On-Vehicle Inspection” in
Section 6E2.
• Poor performance of ECT sensor or MAF
sensor
“ECT Sensor Inspection” or “Mass Air
Flow (MAF) and Intake Air Temperature
(IAT) Sensor Inspection” in Section
6E2.
Faulty injector(s) “Table B-1 Fuel Injector Circuit Check”
in this section.
Faulty ECM
Engine not at normal operating temperature
Clogged air cleaner
Vacuum leaks
VVT system out of order “Oil Control Valve Inspection” in Section
6E2.
Excessive nitrogen
oxides (NOx) emis-
sion
Improper ignition timing “Ignition Timing Inspection” in Section
6F2.
Lead contamination of catalytic converter Check for absence of filler neck restric-
tor.
Faulty EGR system “EGR Valve Inspection” in Section 6E2.
Fuel pressure out of specification “Table B-3 Fuel Pressure Check” in this
section.
Closed loop system (A/F feed back compen-
sation) fails
• Faulty TP sensor “TP Sensor On-Vehicle Inspection” in
Section 6E2.
• Poor performance of ECT sensor or MAF
sensor
“ECT Sensor Inspection” or “Mass Air
Flow (MAF) and Intake Air Temperature
(IAT) Sensor Inspection” in Section
6E2.
Faulty injector(s) “Table B-1 Fuel Injector Circuit Check”
in this section.
Faulty ECM
VVT system out of order “Oil Control Valve Inspection” in Section
6E2.
Condition Possible Cause Reference Item