One problem related to engine rattling and whining sounds has been reported for the 2007 Nissan Sentra. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2007 Nissan Sentra based on all problems reported for the 2007 Sentra.
I have a 2007 Nissan Sentra with 53,000 miles. Started making loud rattling noises when turning to right and when cold to start. Started to get very scary and took into mechanic, since Nissan charges $120 just to diagnose, even if under warranty. Mechanic said it was the right motor mount and was extremely unusual to see with such low mileage. I spoke with a friend that worked at Nissan dealership and he said it always happens, and should be a recall. I spoke to corporate, and they refuse to help at all. This should never happen when you take good care of your car and have low mileage. I will never buy Nissan again.