Linda Martin says she has no idea what caused her car to burst into flames Wednesday afternoon at the River Park Hospital parking lot, damaging two other vehicles and a motorcycle with it."It had been parked there for a hour and a half, maybe two hours," said Martin while surveying the damage Thursday. "It's been driving fine and I kept it serviced regularly. By all accounts, it was running good."Fire investigators with McMinnville Fire Department were on the scene Thursday and say the fire originated in the passenger compartment area.