The last couple of mouths maybe two or three times now when I first start my g35 coupe 90k I get a clicking sound in the engine and dark exhaust, the it goes away. What could be going on?

I'm an enthusiastic driver of an Infiniti G37 Journey sedan. A luxury sports sedan that features a powerful 328HP V-6 engine, a sportier suspension, and a seven-speed automatic transmission with rear-wheel drive; that hits all marks of a sports car in a sedan. The G37 exceeds with advancements in the VVEL engine, which gives up nothing in performance over the coupe. The sedan adds four-door accessibility for passengers.The 7-speed AT has adaptive shift control, drive-sport mode, and downshift rev matching, and these can offer the driver a control similar to a sports car with manual transmission, that other most sedans can't match.