What does it mean when an OBD fault causes torque limitation?
2 Answers
An OBD fault causing torque limitation refers to the exhaust pollutants exceeding the standard. The OBD system continuously monitors the engine's operating condition to check if the vehicle's exhaust exceeds the standard. Below are specific details about the OBD system: Definition: OBD stands for On-Board Diagnostics, which translates to a detection system extended for automotive fault diagnosis. Working Principle: The OBD system continuously monitors the engine's operating condition to check if the vehicle's exhaust exceeds the standard. If it does, it will immediately issue a warning. When a system fault occurs, the malfunction indicator lamp or Check Engine warning light will illuminate, and the Powertrain Control Module (PCM) will store the fault information in memory. The fault code can be read from the PCM through a specific procedure.
I've encountered many OBD faults during car repairs, and it's quite common for them to trigger torque limitation issues. Simply put, when the onboard diagnostic system detects engine problems—such as excessive emissions or sensor errors—the vehicle's computer automatically reduces torque output to prevent further engine damage. This torque limitation makes the car feel sluggish and struggle with uphill driving, but it's a safety measure to avoid breakdowns. Common causes include issues with the aftertreatment system or control module failures. Using an OBD scanner to read the trouble codes can quickly pinpoint the problem for repair. Don’t delay, as it may worsen and lead to costly engine overhauls.
