Hey guys so this week it was the coldest it's been all winter for this area with the lows hitting around 30 degrees and I'm not sure if this is causing the problem or initiated it but this is when I first started experiencing it. Started my car Tuesday morning started driving and there was like a bobbing, kind of like something was loose on both the gas and brake pedal after about 5-10 mins when the car warmed up it went away and it's been pretty much consistent all week after that. It's 2014 sv and I just hit 17k miles. Anyone experience something of this nature before?! On a side note that shouldn't have an effect on that issue I was cleaning the engine bay and everything yesterday and noticed that the coolant reservoir was below the min level ( car had been sitting over night) and I had brought it to Nissan about a month ago and they said everything was good for the 15k check up. Is this something to be alarmed about? Thank you in advance for your input/advice!