If drugs were found in your car, even if they were not yours, you're arrested, obviously so it is a major concern. You absolutely need to have an experienced Pennsylvania criminal defense attorney in your corner from as early as possible in the process. The car is yours. Questions to be asked would be, were other people in the car? Where were the drugs found?
Who was closest in relation to the drugs? Where were you sitting? Where were other people sitting? Were the drugs found in a compartment in the car, or on the floorboard? Were they found in a person's bag if other people were in the car? Was there identifying information in the person's bag, for example, that would not connect the drugs to you, but rather that person?
There are various questions that would need to be asked and answered. An experienced Pennsylvania, criminal defense attorney would be able to help you best understand where you stand in terms of the case and how to best respond to the charges to help you best defend against allegations of this nature. They'll also be able to help you understand and navigate the criminal process.