Two problems related to engine knocking noise have been reported for the 2001 Ford Mustang. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Ford Mustang based on all problems reported for the 2001 Mustang.
There is a rattling, banging noise coming from under the hood. It only did it at first when I was slowing down with and without the brakes. It sounds as though the car is falling apart. I took it to Ford and they told me they heard the noise but it was nothing mechanical and they didn't know what it was coming from. They told me they checked all of the parts under warranty and it wasn't that. They told me that if I wanted them to continue to look for the problem, they would have to charge me by the hour. The car started making the noise about 6 months ago. It will go away for a few days and then come back worse. Now it does it when the car is stopped also. No one can find the problem.
At 7,853 miles, the engine started making a knocking noise. Upon checking the dip stick, the stock was twisted out of shape, giving a reading of more oil than needed. The first service center that I took the car to stated that the car had 1 quart of oil, and could burn 1 quart of oil per 1,000 miles when new (nowhere was this noted in owner's manual, which recommends oil changes every 5,000 miles). Oil change was performed, which did not remedy the situation. The next dealer that the car was taken to identified that the #8 bearing was worn, which required the engine to be replaced. Ford would not honor their warranty, nor would the dealer or the customer service center in michigan answer any of the owner's questions, except that they would not cover the engine. Owner was left purchasing a new engine on their own.