steering problem

[breaker103]

i have a 92 240sx that has power steering and the hicas thing which i know nothing about. when i am accelerating or crusing the steering is fine but if brake mildly the steering gets loose and jerks to the curve of the road. but if i let off the brakes the steering tightens back up and it comes back to normal

plz anyhelp will be apreciated... i promissed my dad i would give him my old car now he is pushing for it plz help
Modified by breaker103 at 1:44 AM 1/10/2009