If you are getting no where with the service manager, ask to see the General Manager or Owner. Ask if the dealer, on your behalf, to contact his rep. If you are being reasonable and civil about your problem, having the dealer act as your advocate will pay dividends. Call the manufacturers Customer Relations department if these don't work.
Every manufacturer has some type of arbitration process or dispuit resolution board.
You should have received information on this in your owners packet when you got the car. If not, ask for a copy of this. Follow directions on this and file. The first non-conformity has to present itself within the first 18 months or 18,000 miles. This may vary state to state.