Goodday sir/madam I am haveing.

Goodday sir/madam

I am haveing serious power problems with my mazda protege when the vehicle reaches 30 mph the hold light on the dashboard starts blinking, the vehicle is also reving but hardly moveing, I nead to rev to at least 4 to get 60 to 80 mph out of it also when I go past 4 the car starts to buck, I have changed the throttle body sensor, speed sensor, oil, plugs, filter and the problem still persists, also note the veicle runs for about half hour with the air sensor unpluged