Chosen Solution
Power steering on 2002 Altima 2.5 is pusing. Seems to be only working for a second then like manual then power etc
You really need to take this to the dealer to have the p/s system tested with a pressure tester to determine if it’s the pump or the steering gear; it could be either. Otherwise you can only “throw” parts at it. I’m assuming the fluid level is OK?
Whenever the steering becomes stiff, the first port of call is the steering fluid reservoir, for the sake of a few £’s or $’s you can simply top up the reservoir to the required point and normal service is resumed! If this fails then you need a better informed opinion such as a garage!