6A±6
ENGINE MECHANICAL
Rough Engine Idling or Engine Stalling
ConditionPossible causeCorrection
Trouble in fuel injection systemIdle air control valve defectiveReplace
Throttle shutting off incompleteCorrect or replace
Throttle position sensor circuit open
or shortedCorrect or replace
Fuel injector circuits open or shortedCorrect or replace
Fuel injectors damagedReplace
Fuel pump relay defectiveReplace
Mass Airflow Sensor circuit open or
poor connectionsCorrect or replace
Mass Airflow Sensor defectiveReplace
Manifold Absolute Pressure Sensor
circuit open or poor connectionsCorrect or replace
Manifold Absolute Pressure Sensor
defectiveReplace
Engine Coolant Temperature Sensor
circuit open or poor connectionsCorrect or replace
Engine Coolant Temperature Sensor
defectiveReplace
Intake Air Temperature sensor circuit
open or poor connectionsCorrect or replace
Intake Air Temperature sensor
defectiveReplace
Knock Sensor (KS) cable broken or
poor connectionsCorrect or replace
KS defectiveReplace
KS Module circuits open or groundCorrect or replace
KS Module defectiveReplace
Vehicle Speed Sensor circuit open or
shortedCorrect or replace
Vehicle Speed Sensor defectiveReplace
Trouble in emission control systemPowertrain Control Module defectiveReplace
Exhaust Gas Recirculation Valve
circuit open or poor connectionsCorrect or replace
Exhaust Gas Recirculation Valve
faultyReplace
Canister purge valve circuit open or
poor connectionsCorrect or replace
Canister purge valve defectiveReplace
Evaporative Emission Canister
Purge control valve defectiveReplace
Trouble in ignition systemRefer to ªHard Startº
6A±7
ENGINE MECHANICAL
Condition CorrectionPossible cause
OthersEngine lacks compressionRefer to ªHard Startº
Valve incorrectly seatedLap valve
Air Cleaner Filter cloggedReplace filter element
Valve timing incorrectReadjust
Idle air control valve brokenReplace
Fast idle solenoid defectiveReplace
Positive Crankcase Ventilation valve
defective or cloggedReplace
Rough Engine Running
ConditionPossible causeCorrection
Engine misfires periodicallyIgnition coil layer shortedReplace
Spark plugs foulingClean or install hotter type plug
Spark plug(s) insulator nose leakingReplace
Fuel injector(s) defectiveReplace
Powertrain control module faultyReplace
Engine knocks periodicallySpark plugs running too hotInstall colder type spark plugs
Powertrain control module faultyReplace
Engine lacks powerSpark plugs fouledClean
Fuel injectors defectiveReplace
Mass Airflow Sensor or Intake
Airflow Sensor circuit defectiveCorrect or replace
Manifold Absolute Pressure (MAP)
Sensor or Manifold Absolute
Pressure Sensor circuit defectiveCorrect or replace
Engine Coolant Temperature Sensor
or Engine Coolant Temperature
Sensor circuit defectiveCorrect or replace
Powertrain Control Module faultyReplace
Intake Air Temperature Sensor or
Intake Air Temperature Sensor
circuit defectiveCorrect or replace
Throttle Position Sensor or Throttle
Position Sensor circuit defectiveCorrect or replace
Knock Sensor or Knock Sensor
circuits defectiveCorrect or replace
Knock Sensor Module or Knock
Sensor Module circuits defectiveCorrect or replace
