2007 impreza loses throttle while driving

[AlaskanWookie]

Driving to work today, and while on the highway I just lost throttle. It would Rev up but had almost no movement forward. It sounded weaker than normal. Pulled over, disconnected the battery and then connected it again. Went away, drove some more and it came back like 10 minutes later. Same thing worked and I was off again. Any idea? No engine light haven't plugged into it to see if there's a code that just not popping up. Seems like a sensor issue but which? Throttle body sensor? It's a manual if that makes a difference. The cruise control light flashes all the time as well.

 

[bmart]

RPM increases but car doesn't go faster? Clutch seems likely if that's true.