[svxthc]

Lately my car has been taking progressively longer to start- around 3-4 seconds. Today it made a funny sound like a jet engine shutting off when I went to start it. Usually after it starts, especially in cold weather, the thing whines like a sewing machine under throttle especially while it is heating up. Also, the exhaust shields sound like they are loose because I hear a tinny sound at 2-3k rpm. Is it time I replace the spark plugs perhaps? The car has gone 75k and god knows how long its been. Any ideas? Time to take it in while still under dealer warranty?