Hiken

When i start the car in the morning, put in direct and hold the break, the rpms begin to fluctuate up and down, the rpms dont go above 800, the lowest ive seen it drop is 500 and go back to 800 and the car dies within a minute, i have no issues starting it back again, same thing in reverse. On parking mode only the rpms fluctuate but the car doesnt die off, this all happens on cold engine. Once the engine is warm it doesnt seem to happen, it sits at 800 without any fluctuation