I think your AC compressore is choked brother... get it inspected from a good AC mechanic.. secondly, when ever you buy a second hand car, make sure you properly tune up the car from iether the company or professional workshops... e.g. throttle body, plugs, cng kit, fan belts, timing belts, all these things must be checked if you want your car engine to be long life..
Now go and get your AC checked from a good AC mechanic, if the propblem still exists then go to honda pitshop.. thats it.. dont waste time with some stupid so called mechanics...