on our 2013 Elantra we're having intermittent problems with the engine losing power while driving and the tachometer reading "0", yet the engine is still running. had to turn off and on about 4 or 5 times this evening to get the car to "reset" itself. usually happens around 35-55 mph but this evening it happened while at a stoplight. anyone have any idea what the problem may be. i've heard about the crankshaft sensor issue. could this be what's going on? we recently received a message from our local dealership about a safety bulletin about an "engine control module". could this be the issue? car has approx 77,000 miles on it. thanks for all reads and replies!!!