Possible causes – Faulty Crankshaft Sensor– Crankshaft Sensor harness is open or shorted– Crankshaft Sensor circuit poor electrical connection– Faulty Ignition Control Module When is the code detected? The Powertrain Control Module (PCM) detects a predetermined amount of high resolution

Possible causes – Faulty Cylinder Deactivation Solenoid– Cylinder Deactivation Solenoid harness is open or shorted– Cylinder Deactivation Solenoid circuit poor electrical connection When is the code detected? The control module detects that the actual measured values from the MAF sensor,

Possible causes – Faulty Cylinder Deactivation Solenoid– Cylinder Deactivation Solenoid harness is open or shorted– Cylinder Deactivation Solenoid circuit poor electrical connection When is the code detected? The control module detects that the actual measured values from the MAF sensor,

Possible causes – Faulty Cylinder Deactivation Solenoid– Cylinder Deactivation Solenoid harness is open or shorted– Cylinder Deactivation Solenoid circuit poor electrical connection When is the code detected? The control module detects that the actual measured values from the MAF sensor,

Possible causes – Faulty Cylinder Deactivation Solenoid– Cylinder Deactivation Solenoid harness is open or shorted– Cylinder Deactivation Solenoid circuit poor electrical connection When is the code detected? The control module detects that the actual measured values from the MAF sensor,

Possible causes – Faulty Cylinder Deactivation Solenoid– Cylinder Deactivation Solenoid harness is open or shorted– Cylinder Deactivation Solenoid circuit poor electrical connection When is the code detected? The control module detects that the actual measured values from the MAF sensor,

Possible causes – Faulty electric throttle control actuator (TP sensor 1 and 2)– Throttle Position Sensor harness is open or shorted– Throttle Position Sensor circuit poor connection– Faulty accelerator pedal position sensor Symptoms – Engine Light ON (or Service Engine

Possible causes – Faulty Engine Coolant Temperature (ECT) sensor– Low engine coolant level– Engine Coolant Temperature (ECT) sensor harness is open or shorted– Engine Coolant Temperature (ECT) sensor electrical circuit poor connection– Faulty engine coolant thermostat Symptoms – Engine Light

Possible causes – Faulty Engine Coolant Temperature (ECT) sensor– Low engine coolant level– Engine Coolant Temperature (ECT) sensor harness is open or shorted– Engine Coolant Temperature (ECT) sensor electrical circuit poor connection– Faulty engine coolant thermostat Symptoms – Engine Light

Possible causes – Faulty Engine Coolant Temperature (ECT) sensor– Low engine coolant level– Engine Coolant Temperature (ECT) sensor harness is open or shorted– Engine Coolant Temperature (ECT) sensor electrical circuit poor connection– Faulty engine coolant thermostat Symptoms – Engine Light

Possible causes – Faulty Engine Coolant Temperature (ECT) sensor– Low engine coolant level– Engine Coolant Temperature (ECT) sensor harness is open or shorted– Engine Coolant Temperature (ECT) sensor electrical circuit poor connection– Faulty engine coolant thermostat Symptoms – Engine Light

Possible causes – Faulty Engine Coolant Temperature (ECT) sensor– Low engine coolant level– Engine Coolant Temperature (ECT) sensor harness is open or shorted– Engine Coolant Temperature (ECT) sensor electrical circuit poor connection– Faulty engine coolant thermostat Symptoms – Engine Light

Possible causes – Faulty Engine Coolant Temperature Sensor– Engine Coolant Temperature Sensor harness is open or shorted– Engine Coolant Temperature Sensor circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1119 GMC Description The

Possible causes – Faulty Engine Oil Pressure Switch– Engine Oil Pressure Switch harness is open or shorted– Engine Oil Pressure Switch circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1189 GMC Description The

Possible causes – Faulty EVAP canister purge solenoid– Faulty Fuel Tank Pressure (FTP) sensor When is the code detected? The Powertrain Control Module (PCM) has detected vacuum flow to the Fuel Tank Pressure (FTP) sensor during a system sealed condition.

Possible causes – Faulty EVAP Purge Solenoid– EVAP Purge Solenoid harness is open or shorted– EVAP Purge Solenoid circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1655 GMC Description The Powertrain Control Module

Possible causes – Faulty EVAP Vent Solenoid– EVAP Vent Solenoid harness is open or shorted– EVAP Vent Solenoid circuit poor electrical connection When is the code detected? The Powertrain Control Module (PCM) has detected the EVAP Vent Solenoid circuit was

Possible causes – Faulty Exhaust Gas Recirculation (EGR) valve– Carbon blockage of the pintle Tech notes On some models, there is a service bulletin for the P1404 code that suggest reprogramming the Powertrain Control Module (PCM) to repair the problem.

Possible causes – Faulty Exhaust Gas Recirculation (EGR) valve– Carbon blockage of the pintle Tech notes The P1406 code means that the EGR valve is 10% of the expected position by the Powertrain Control Module (PCM), usually caused by carbon

Possible causes – Faulty Front Oxygen Sensor– Front Oxygen Sensor harness is open or shorted– Front Oxygen Sensor circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1132 GMC Description A Heated Exhaust Oxygen