Honda of Toms River Doesn't Honor Warranty

I bought a used car; a 2006 Ford Explorer from this car dealership. When I test drove it, it had a low tire pressure sensor warning light on the dash. The salesman Sal L. said it was no problem and they would fix it for me. So I bought the car. Then a couple of days later when I picked up the car, it still had the warning light on. Sal said no problem that they filled the tires but it must be a bad sensor and I had to schedule a visit with their service department. A few days later I brought the car in for service and after having the car for two days, Rita in the service deptartment said they weren't able to fix it and they had to have a Ford dealership fix it and they would pay for it. But it required a manager's approval. It has been three weeks with me calling every other day to both the service manager Rick Holt and the sales manager Mark Stango and no one will return my calls. And no one else can help me. The car has now overheated twice in addition to the low tire pressure sensor problem. Good luck getting them to take car of it under warranty; which I have but they won't honor.