Carenado Mooney autopilot problem

I haven't flown fs2004 for awhile, and I'm not sure where I picked up this problem:When in altitude hold mode on the AP, my plane bounces up and down and won't hold altitude. The vs goes from -700 to +700. It just constantly overcorrects. It doesn't seem like the regular turbulence or vertical winds from ActiveSky. I know there are some things I can edit, but I wanted to see the best way to fix this.