Your Opel Commodore engine control system detects a problem, the computer stores the diagnostic trouble
code P3078 in its memory.
To figure out what is wrong with your vehicle you must first extract the P3078 DTC For Opel Commodore.
On 1999 and later P3078 Opel Commodore engines, the instrument cluster has a built-in self-diagnostic mode that can be accessed by pressing and holding the instrument cluster SELECT/RESET button. Insert the ignition key and turn to the RUN position (but don't crank or start engine). Continue to press and hold the SELECT/RESET button (for 5 seconds) until the word TEST is displayed by the odometer. Release the SELECT/RESET button within three seconds after the word TEST is displayed to begin the self-diagnostic mode.
P3078 Opel Commodore DTC Meaning
Powertrain Code - Problem is related engine, transmission and emissions systems.
SAE - Generic
Exhaust Gas Recirculation System Valve 1
Park/Neutral Postion (PNP) Switch Circuit Engine Torque Signal Circuit
The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. P3078 Opel Commodore code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.