Methods and systems are provided for reliably prognosing a vehicle component, such as a vehicle battery or an intake air filter. A state of degradation of the component is predicted based on a metric that is derived from a sensed vehicle operating parameter, the parameter selected based on the component being diagnosed, as well as based on past driving history and future driving predictions. The predicted state of degradation is then converted into an estimate of time or distance remaining before the component needs to serviced, and displayed to the vehicle operator.