Automatic Transmission Control Module problems of the 2017 Hyundai Elantra

The vehicle has experienced ongoing powertrain and electrical malfunctions over several months. The most common symptoms include being stuck in 4th gear (limp mode), complete loss of rpm and speedometer readings, and illumination of the check engine and esc lights. Most recently, while traveling at approximately 10 mph, the vehicle experienced a sudden loss of both acceleration and braking. The brake pedal became stiff and unresponsive, and the car had to coast to a stop without driver control. This posed a serious safety risk to myself and nearby traffic. These issues have persisted across multiple service visits to ricart Hyundai in groveport, ohio. That dealership has replaced the crankshaft position sensor three times, the powertrain control module (pcm), and the battery, but the underlying problems remain unresolved. A technician at the dealership was able to reproduce the stalling event during a test drive. Despite that, the dealership has refused to proceed with further diagnostics unless I pay for an oil change, even though previous inspections by their own staff found no visible leaks and confirmed the oil level was sufficient at the time. They have also revoked complimentary access to a loaner vehicle despite the unresolved and unsafe condition of the car. The vehicle remains available for inspection. The problem has been confirmed by a dealership, has occurred repeatedly, and continues to pose a safety concern. Warning lights and gauge failures typically appear when the issue occurs.

According to the Hyundai dealership, located in corona, CA, the Hyundai Elantra's are known for the ignition coil to go out. This is also not covered under warranty and list below of why it should this can cause engine misfiring in a vehicle whose ignition coils have failed. Trying to start the engine of such a vehicle will result in engine misfiring that sounds like a coughing, sputtering noise. When driving at high speeds, jerking and spitting will be seen in the behavior of the vehicle. A vehicle with a failed ignition coil will also result in vibration when it is idling at a stop sign or light. Driving with a faulty coil pack can damage other components of the engine. Also most cars will register a faulty coil and immediately stop gas feed to that cylinder. However, damage may be caused if the fault isn’t registered by the pcm and the dead cylinder continues to receive gas. Your catalytic converter and oxygen sensors may become contaminated by raw gas and need to be replaced. This can be dangerous if it is a known common issue in a Hyundai Elantra and cause an accident when travelling at a higher speed. I was at a stop when this problem occurred for me but was able to safely move out of the way.