Possible causes – Faulty Manifold Absolute Pressure sensor– Manifold Absolute Pressure harness is open or shorted– Manifold Absolute Pressure sensor circuit poor electrical connection– Faulty Engine Control Module (ECM) When is the code detected? An excessively low voltage from the

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty Park/Neutral Position Switch– Misadjusted Park/Neutral Position Switch– Park/Neutral Position Switch harness is open or shorted– Park/Neutral Position Switch circuit poor electrical connection When is the code detected? The transmission range switch detects the selector lever position

Possible causes – Faulty Powertrain Control Module (PCM)– PCM harness is open or shorted– PCM circuit poor electrical connection– PCM Programming Tech notes Check the Powertrain Control Module (PCM) fuse, if fuse is OK try erasing the code first and

Possible causes – Faulty Powertrain Control Module (PCM)– Powertrain Control Module (PCM) harness is open or shorted– Powertrain Control Module (PCM) cicuit poor electricl connection– Low battery voltage Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P0601

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 1– Rear Heated Oxygen Sensor Bank 1 harness is open or shorted– Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection– Inappropriate fuel pressure– Faulty fuel injectors– Intake air leaks

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 1– Rear Heated Oxygen Sensor Bank 1 harness is open or shorted– Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection– Inappropriate fuel pressure– Faulty fuel injectors– Intake air leaks

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 1– Rear Heated Oxygen Sensor Bank 1 harness is open or shorted– Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection– Intake air leaks– Exhaust gas leaks– Inappropriate fuel pressure–

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure – Faulty fuel injectors– Intake air

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure – Faulty fuel injectors– Intake air

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure– Faulty fuel injectors– Intake air leaks

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure– Faulty fuel injectors– Intake air leaks

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure– Faulty fuel injectors– Intake air leaks

Possible causes – Faulty Reverse Inhibit Solenoid– Reverse Inhibit Solenoid harness is open or shorted– Reverse Inhibit Solenoid circuit poor electrical connection When is the code detected? When the Reverse Inhibit solenoid energizes, the operator can shift the transmission into

Possible causes – Faulty Skip Shift Lamp– Skip Shift Lamp harness is open or shorted– Skip Shift Lamp circuit poor electrical connection When is the code detected? When the Powertrain Control Module (PCM) commands the control circuit to a component

Possible causes – Faulty Skip Shift Solenoid– Skip Shift Solenoid harness is open or shorted– Skip Shift Solenoid circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P0803 BUICK Description An ignition voltage is

Possible causes – Faulty spark plug (s) – Faulty ignition coil (s) – Clogged or faulty fuel injector (s)– Intake air leak– Fuel injectors harness is open or shorted– Fuel Injectors circuit poor electrical connection– Ignition coils harness is open

Possible causes – Faulty spark plug 1– Clogged or faulty fuel injector 1– Faulty ignition coil 1– Fuel injector 1 harness is open or shorted– Fuel injector 1 circuit poor electrical connection– Ignition coil 1 harness is open or shorted–