SAAB 9-5 2001 NEED HELP!!! DONT KNOW WHAT TO DO!?!?

I turned the car on a couple days ago and my TCS turned off and wont turn on. Also my cruise control won't work. My car is either idling to high or to low. My car is in need of an oil change withing a couple hundred miles. Could that be it? I brought it into an auto parts store and they did a scan. There was one code and it was P1251. Any thoughts of what i should do. I am not about to take it into the dealership again because they just **** me around. HELP PLEASE! WHAT SHOULD I DO?!