I have a Yamaha Gas Golf that runs but only goes 1 mph. In neutral you can have the gas pedal press half way and it runs a little faster but its in neutral. When it passes the half mark, it just slows back down. In drive it goes slow. roughly 2 mph. very slow, but will go. i just replaced the gas pump and gas goes into the engine. The engine shows 150 pounds of compression. So what’s wrong?