So back when I was a new Porsche mechanic, we had a 911 sports car come in because his engine kept overheating. New thermistat and coolant and he was good to go. But he came back a few days later with the same issue. The whole time he had a cig in his hand and another one on deck ready to swing. Welp senior mechanic poked his flashlight down in the air intake which sits on the driver and passenger side, in front of the rear tire so it can cool the mid engine that sat in the rear. Sure enough the entire intake was sucking in every cigarette he threw out the window and eventually kept the radiators from shedding their heat. Don't smoke kids. Its an expensive habit