Gas Recirculation Valve (egr Valve) problems of the 2013 Chevrolet Spark

Takata recall: I purchased this vehicle oct 9 2015 with 56k miles on it. From the day I purchased it up to today I have been hearing a humming/buzzing/whistling noise coming from the rear of the vehicle. I had it checked out by a repair shop and was told it was a faulty fuel pump with an estimated cost of $500. The noise can be heard only when the car is on and running and it can be heard inside and outside of the vehicle when stopped or moving. It can be heard from inside and outside the vehicle and has only got worse since the day I purchased it. I am a part time uber driver and I own a mobile cell phone repair business and I am in my running vehicle up to 15 hrs/day. I have researched this issue and there are many threds and blogs online with customers complaining of the same issue. I do not feel I should be responsible for this repair charges has the vehicle was making this noise soon after the purchase and I was not notified. This noise has started to affect me mentally as there is nothing I can do to drown it out. I is also starting to affect the performance of the vehicle. Please help. "takata recall" also, since the purchase of this vehicle I have noticed the ac does not blow cold air when sitting at an idle. I live in arizona and temperatures can reach 120 degrees. As I mentioned I am in my vehicle up to 15 hrs/day and many of those hours are spent sitting idling while I repair my customers cell phones. When I am sitting in 120 degree heat with barely cool air blowing on me it makes it about 90 degrees in my vehicle which can cause health issues and worst case scenario death. I am at the verge of selling this vehicle, obtaining a lawyer, and filing a complaint or law suit, especially if my health is being affected. Please help.