Throttle help

Hey guys. Got a 2014 170 and it is not running correctly. First I noticed that when my son put it in gear it would jump a little. Still running correctly at that time just seemed to be idling high. He was able to ride it like that for a short while.

Now it will still jump but then thats it. I have zero throttle response. I took the throttle box off and made sure the cable is connected. Then I took the throttle cable out of the carb. Hope I didn’t screw up there. Press the gas petal and It seemed I only had around 1/4" movement. Is this correct? With any movement at all I don’t think the cable is broken. Any one have any idea’s? Thanks for any info!