Engine Controls - Trouble Shooting - No Codes: Symptoms

SYMPTOM DIAGNOSIS CHART

Symptom

⁽¹⁾ Possible Cause

Engine Stalls During Idle

Idle Air Control Solenoid Valve,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
Mass Airflow Sensor,
⁽²⁾ Ignition Parts,
⁽³⁾ Engine Coolant Temperature Sensor,
⁽⁴⁾ Crankshaft Position Sensor,
⁽⁴⁾ Camshaft Position Sensor,
EGR Valve,
⁽⁵⁾ Fuel Injection Components

Rough Idle

Idle Air Control Solenoid Valve,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
Mass Airflow Sensor,
⁽³⁾ Engine Coolant Temperature Sensor,
⁽²⁾ Ignition Parts,
⁽⁶⁾ Air Intake System,
⁽⁵⁾ Fuel Injection Components,
Throttle Position Sensor,
⁽⁴⁾ Crankshaft Position Sensor,
⁽⁴⁾ Camshaft Position Sensor,
EGR Valve,
Oxygen Sensor,
Fuel Pump,
Fuel Pump Relay

Engine Does Not Return To Idle

Idle Air Control Solenoid Valve,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
Engine Coolant Temperature Sensor,
⁽⁷⁾ Accelerator Cable,
Throttle Position Sensor,
Mass Airflow Sensor

Poor Acceleration

Mass Airflow Sensor,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
Throttle Position Sensor,
⁽⁵⁾ Fuel Injection Components,
Fuel Pump,
Fuel Pump Relay,
⁽³⁾ Engine Coolant Temperature Sensor,
⁽⁴⁾ Crankshaft Position Sensor,
⁽⁴⁾ Camshaft Position Sensor,
A/C Switch,
A/C Relay,
Engine Torque Control Signal Circuit,
⁽²⁾ Ignition Parts

Engine Stalls, Sags Or Hesitates During Acceleration

Mass Airflow Sensor,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
⁽³⁾ Engine Coolant Temperature Sensor,
⁽⁴⁾ Crankshaft Position Sensor,
⁽⁴⁾ Camshaft Position Sensor,
Purge Control Solenoid Valve,
EGR Valve,
⁽⁵⁾ Fuel Injection Components,
Throttle Position Sensor,
Fuel Pump,
Fuel Pump Relay

Surge

Mass Airflow Sensor,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
⁽²⁾ Ignition Parts,
⁽³⁾ Engine Coolant Temperature Sensor,
⁽⁴⁾ Crankshaft Position Sensor,
⁽⁴⁾ Camshaft Position Sensor,
EGR Valve,
⁽⁵⁾ Fuel Injection Components,
Throttle Position Sensor,
Fuel Pump,
Fuel Pump Relay

Spark Knock

Mass Airflow Sensor,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,
⁽³⁾ Engine Coolant Temperature Sensor,
Knock Sensor,
⁽⁵⁾ Fuel Injection Components,
Fuel Pump,
Fuel Pump Relay

After-Burn In Exhaust System

Mass Airflow Sensor,
Intake Manifold Pressure Sensor,
Intake Air Temperature Sensor,⁽³⁾ Engine Coolant Temperature Sensor,
⁽⁵⁾ Fuel Injection Components,
Fuel Pump,
Fuel Pump Relay

⁽¹⁾	Check possible causes in order listed.

⁽²⁾	Check ignitor, ignition coil and spark plugs.

⁽³⁾	If symptom occurs only in cold temperatures.

⁽⁴⁾	Ensure component is securely installed.

⁽⁵⁾	Check fuel injectors, fuel pressure regulator and fuel filter.

⁽⁶⁾	Check for air leak(s) in air intake system.

⁽⁷⁾	Adjust accelerator cable.