^^^This^^^ Is your Volt a used Volt that is new to you?It's just the gas engine (ICE) revving at higher rpm's for needed electric power generation. It'll rev up and down as needed by the car. The ICE is really just a generator. The car is always propelled by the electric motor. So the ICE revving up for seemingly no reason or as you depress the accelerator peddle is normal. Cheers
ICE= Internal Combustion Engine
If it's just the gas generator, it'll take a little getting used to -- unlike a regular ICE car, the engine RPMs on the Volt don't always correspond to how fast your going or how hard you're pushing on the accelerator. It's just based on the electrical load on the car at any given moment.Has anyone had a howling noise when the engine is running. My noise comes from under the hood and is consistent around 42 mph. It will temporarily leave when letting off the gas. It is also intermittent and can come at other speeds.