Leaking, clogged, or incorrectly installed Power Steering hose; Leaking or damaged power steering pump (reservoir); Transmission fluid loss from leaking transmission seal (at firewall).
White exhaust Smoke could also be from: Worn or broken piston rings; Cracked or brittle valve stem seals allowing oil to enter combustion chamber; Rich fuel injector; Plugged or damaged pcv valve; Worn or scored cylinder block (engine); Worn or damaged piston; Worn valve guides.
You might be low on power steering fluid
apparently it already has...
Possibly a worn belt on the power steering pumo.
Possibly, the power steering pressure switch changes the idle if there is more pressure due to use of the power steering it will increase the idle. A bad switch could be sending faulty informatioin causing your idle to be wrong and the car could stall. These switches cost about $30-$35 and depending on location take minutes to change with a couple wrenches.
check your power steering fluid
Possibly the belt driving the power steering pump is worn or loose, and when wet, slips, causing the steering to get stiff.
Alternator Belt has snapped, causing you alternator to stop charging causing you battery light to come on, but this belt also runs your power steering pump which if that's not working your steering will become heavy
This is two of the things I know that could be wrong. The power steering pump is either bad or there is no power steering fluid in the pump causing it to have steering problems. Be sure to check the fluid level in the power steering pump.
The steering wheel in your 1996 may be hard to turn because you are low on power steering fluid. You can add some on your own and your steering wheel will not be hard to turn.
If the gearbox is causing freeplay in the steering wheel, then the gearbox needs to be replaced.
The 2006 Chevrolet Impala had recalls on the 979 steering knuckle and the manual passenger seat adjuster. The steering knuckle recall is due to the possibility of a broken steering knuckle causing a loss of steering.
Worn-out ball joints in the steering linkage or suspension. This allows the steering angle between the wheels to vary, causing them to wobble.