A turbo-charged vehicle is low on power. Which of the following would cause this problem?

A turbocharged vehicle relies on its turbocharger to increase engine power by forcing more air into the combustion chamber. When a turbocharged vehicle experiences low power, multiple factors related to the turbocharger and its components can be involved.

If the turbo wastegate is stuck in the closed position, it prevents the exhaust gases from bypassing the turbocharger, which can lead to an excessive buildup of back pressure and potentially limit the boost pressure. This situation can starve the engine of the needed air for optimal combustion, resulting in reduced power.

Additionally, if the impeller is worn, the efficiency of the turbocharger is compromised. A worn impeller may not be able to compress air effectively, which means less air gets into the engine, leading to lower power output.

Moreover, if the belt that drives the turbocharger is worn or loose, it can slip or fail to transmit the necessary power to the turbocharger effectively. This can contribute to insufficient boost, thereby causing a drop in engine performance.

Each of these issues can individually or collectively contribute to a decrease in the overall power of a turbocharged vehicle. Thus, all listed factors can indeed be potential causes of low power, which supports the selection of the answer as a comprehensive response to the problem.