Is this necessary? I read the DIY and wondered if it could problems if not done properly. Any help would be appreciated.

 

It's only necessary if you have a good amount of mileage on your car and carbon build-up. Cleaning the throttle bodies can be harmless if done properly, but if you do any damage to the butterfly valve or throttle body gasket, it'll cause idling/driving issues or put your car into limp mode.