Detonation/Spark Knock/Pings

SYMPTOM DESCRIPTION:

A mild or severe ping, usually worse under acceleration. The engine makes a sharp metallic knock as engine rpm varies.

SYSTEM OR COMPONENT TO CHECK

COOLING
CHECK: For obvious over heating problems.
FAN OPERATION: Check fan clutch operation. Restricted air flow to radiator or restricted coolant flow.
WATER PUMP: Operation, loose belts.
THERMOSTAT: Faulty or incorrect.
COOLANT: Low engine coolant level and leaks.Correct coolant solution - should be a 50/50 mix of anti-freeze (coolant) and water.

COMPUTER INPUTS/OUTPUTS
CHECK:
IGNITION CONTROL UNIT: Improper wiring or defective control unit
CRANKSHAFT POSITION/SPEED SENSOR: Damaged or improperly installed crankshaft position/speed sensor.

FUEL
CHECK:
LEAN FUEL/AIR MIXTURE: Test fuel pump pressure and volume output.
FUEL INJECTOR: Fuel injector spray pattern, clogged, or stuck injector.
FUEL QUALITY: Poor or contaminated fuel, proper octane rating.

IGNITION
CHECK:
SPARK PLUGS: Proper heat range.
IGNITION CONTROL UNIT: Improper wiring or defective control unit
CRANKSHAFT POSITION/SPEED SENSOR: Damaged or improperly installed crankshaft position sensor

ENGINE/TRANSMISSION
CHECK:
CARBON BUILD-UP: Remove carbon at intake valves.Incorrect basic engine parts such as cam, heads, pistons, etc. Excessive oil entering combustion chamber. Proper transmission shift points.