Detonation/Spark Knock/Pings

DEFINITION
A mild to severe knock, that usually occurs under acceleration, The engine produces sharp metallic sounds that change with throttle opening. Generally higher pitched than an engine knock. May be described as a ticking or clatter noise. Occurs when fuel/air charge is ignited by something other than the spark plug.

POWERTRAIN SYSTEM
Perform Powertrain System Check, if not already completed. Chart 1 Powertrain System Check

EXHAUST GAS RECIRCULATION (EGR)
Check EGR System. Refer to Chart 6EC-1 EGR System Check. Chart 6EC-1 EGR System Check

FUEL SYSTEM
Perform Chart 6C-1 Fuel System Check looking in particular for:

^ Fuel Quality
- Low Octane level
- Contaminants
^ Low Fuel Pressure
^ Low Flow Rate Injector

Chart 6C-1 Fuel System Check

IGNITION SYSTEM
Perform Chart 1 Ignition System Check, looking in particular for:

^ Knock Sensor Not Operating Properly

Chart 1 Ignition System Check

COOLING SYSTEM
Check for cooling system problems, looking in particular for:

^ Overheating Engine
- Depressurized Engine Cooling System
- Restricted Engine Coolant Flow
- Engine Coolant Fans Inoperative

MECHANICAL CAUSES
Check for the following mechanical causes:

^ Excessive Oil Consumption
^ Camshaft Timing
^ Intake Valve Deposits
^ Engine Knock