2001 Nissan Altima

2001 Nissan Altima Manual 100000 miles

Sometimes when I am driving my brakes will get very hard- I barely touch them and it's like I'm slamming on the brakes. During these times my car feels like it is working very hard to drive. It shakes a little and when I take my foot off of the gas (whether I put it in neutral or just press on the clutch) it slows down considerably, like I'm braking-but I'm not. Once during one of these times I was at a stop light at a down hill road and I could sit in neutral and I didn't have to press on the brakes and I was just stopped. Ishould have been rolling down the hill but I was just sitting there. Sometimes my car is perfectly fine with no breaking problems or engine problems. There is no rhyme or reason to the problem. Sometimes it happens in the morning, sometimes evening. Sometimes after driving awhile, sometimes when I first start the car. Sometimes when it's hot, sometimes cold.