This is the reading that appears on the dash read out. It typically indicates this when the engine water cooling system over heats, but I have no over heating occuring, the water pump is not leaking or failing in any manor and the engine is not over heated at any time. When the engine goes to the "engine power down" the vehicle cut down to less than 15% of it power so you speed drops according. This a design GM uses to get you off the road safely at a random firing of less cylinders, which is great, unless there is a sensor that is generating a false indication which is my suspision.
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