That looks to be the what they call the air temp sensor. It also acts as the mass airflow sensor...and it needs to be functioning correctly to run correctly. Why anyone would just cut the sensor lead is not only pure stupid..but very costly in time and money if one was to replace the entire harness just for that. Finding a plug end for that particular sensor might be problematic.. but worth a look. It should also be known that that sensor is notorious for getting contaminated with either oil from over-oiled foam filters or just plain dust from OE filters and when it is, sends bad info to the ECU. They can be cleaned..but only with only mass air flow sensor cleaner. But when someone uses something else, it destroys the unit and can not be saved. So..get a new one anyway and look for an end. The using a wiring diagram you can hook it back up correctly. Good luck
Oh, you can buy an entire wiring harness from any CFM parts house or Alpha-Sports.com. Be prepared to strip it down to the frame to install it though.