GMC Savana 3500 lost power, won't move forward or backward despite engine running fine on GMC Savana 3500

Some GMC Savana 3500 owners report experiencing a loss of power that prevents the vehicle from moving forward or backward, even though the engine appears to be running fine. These issues may stem from a faulty throttle position sensor, which can illuminate the check engine light and trigger a reduced power message along with OBD trouble code P2135. Additionally, a malfunction in engine management sensors or the Engine Control Unit (ECU) may also result in a reduced engine power warning. Electrical wiring problems related to the engine control module (ECM) could further contribute to this reduced power mode. Other potential causes include a clogged air filter, faulty fuel pump, malfunctioning throttle position sensor, or a clogged catalytic converter, all of which can lead to the engine idling without the ability to accelerate. It is essential for owners experiencing these symptoms to address these potential issues promptly for effective diagnosis and resolution.