Just purchased 2000 VW Jetta. After driving 3000 miles, oil indicator on, no oil on dip stick when checked. Changed oil and found foam on oil cap and dip stick. Dealership said normal and could expect to use up to 1 qt oil per every 1000 miles and to change the oil every 5000 miles. Said foam due to low mileage. Is anyone familiar with this and is it normal?????