I have a 2012 Hyundai Elantra and lately when I am going around 40 km/hr I will push the gas but my car won't accelerate. I take my foot off the gas for a second and try again and it works. Yesterday my tachometer stopped working as well but when I turned the vehicle off and turned it on again it was working. I had taken it to the mechanics last week and they only found one code showing up and when they reset it, it never came back - basically they couldn't find anything wrong. The code was C1611 control area network. Any help would be appreciated!