We purchased this 04 48" WB back in November. The engine only starts when you put the choke on despite how long it's running. Once it's on, it idles fine. However, the moving the throttle seems to have little/no impact on the engine speed. It doesn't ever get up to a higher speed. Everything seems attached and moving on the outside of the engine, so I'm at a loss for what the cause could be. Any ideas from my terrible description?