Low Power Steering fluid. Low engine speed. Air in power steering pump. Turn steering wheel to maximun left and maximum right several times. Check fluid.
Variable power steering assist is an electrical system and can be affected by the neutral safety - start switch, which is also known as the transmission range sensor.
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There is a problem with the emissions system.
I had the same problem, water was entering around lamp, sealing around perimeter worked for me.
One cause of a popping noise from the front end while backing up in cold weather is the drive shaft. A mechanic can help find the problem.
my dodge has the same problem, it is the power steering return hose being cracked or cut.
I don't know, but I have the same problem with my 2011 Sentra. :(
If it only happens when backing up, you may have the parking brake engaged.
it wiil break your steering column
Does it turn over??
One common problem is a faulty steering position sensor. This $60 sensor, located at the base of the steering column (inside the vehicle), tells the variable assist power steering how fast you are turning the steering wheel. When faulty, it will cause lurching and surging in the steering - feels like loose parts.
The popping sound is most likely caused by a problem with the suspension. The front strut spring is the most likely culprit.
I had a 1990 nissan maxima that use to do that and the problem was my rack and pinion bushings were bad
Failure of the Power Steering system.