Power steering 89 chevy

Sounds like the high pressure power steering hose is leaking. Check it out and if so replace it along with the low pressure return line. If the lines are not leaking then the power steering pump could be the problem.

Get manual online under $10-15 and get complete guide on whether to repair or not, service it, and how to repair etc

you can get it from reliable-store or manualslife
really good plus instant help also available

check the tension of the belt driving the power steering pump if not real tight it needs replaced turn wheel all way to left then to right listen for a squeeling noise if squeels then you need new power steering pump

There is a "pressure regulator" located in the pump just behind the high pressure line that directs high pressure fluid to the steering rack when you turn the steering wheel. It sounds like the regulator valve is sticking and not sending the high pressure fluid to the steering rack when you turn the wheel.
You can remove the pump and clean the valve, reinstall the pump and flush the steering system with fresh fluid or replace the pump and flush the system with new fluid.
Good luck.

FIRST OF ALL YOU HAVE TO REMOVE POWER STEERING FLUID.USING A SUCTION GUN OR LARGE SYRINGE.REMOVE MUCH FLUID AS POSSIBLE.WHEN DONE REMOVING POWER STEERING FLUID.YOU NEED A INLINE WRENCH AND OPEN BOX END WRENCH TO REMOVE THE POWER STEERING HOSE.YOU HAVE TO REMOVE POWER STEERING LINE FROM THE RACK.UNDER THE CAR SAFELY RAISE AND SUPPORT VECHICLE. THEN REMOVE THE TIRE OR WHEEL.THEN REMOVE THE INNER FENDER SPLASH SHIELD.ITS GOING TO BE A TIGHT FIT AND HARD PLACE TO GET YOUR HAND TO REMOVE THE POWER STEERING LINE FROM BOTTOM.WHEN DONE.MAKE SURE NEW POWER STEERING HOSE OR LINE HAS NEW O RINGS.WHEN INSTALLING THE THE NEW STEERING HOSE.WHEN ALL IS DONE BLEED POWER STEERING SYSTEM. FILL UP POWER STEERING PUMP TO CORRECT FLUID LEVEL.THEN LET IT SET FOR 2 MINUTES UNDISTURBED.THEN START THE ENGINE RUN IT FOR 2 TO 3 SECONDS.ONLY CHECK THE RESERVOIR AND ADD MORE FLUID AS NECESSARY.REPEAT THE OPERATION UNTIL THE FLUID LEVEL REMAIN CONSTANT.NOW RAISE FRONT OF THE CAR UNTIL THE WHEELS CLEAR THE GROUND START THE ENGINE AND INCREASE THE SPEED TO ABOUT 1500 RPM.NOW TURN THE STEERING WHEEL GENTLY FROM STOP TO STOP CHECK THE FLUID LEVEL.LOWER THE VECHICLE TO THE GROUND WITH ENGINE STILL RUNNING MOVE THE CAR FORWARD SUFFICIENTY TO OBTAIN FULL RIGHT LOCK FOLLOWED BY FULL LEFT LOCK BUT DONT HOLD THE SREERING WHEEL FIRMLY AGAINST THE STOPS.RECHECK THE FLUID LEVEL IF THE FLUID IN THE RESERVOIR IS EXTREMELY FOAMY ALLOW THE CAR TO STAND FOR A FEW MINUTES.WITH ENGINE OFF.WHEN JOB IS FINISH. WARNING DONT DRIVE CAR ON ROAD IF YOUR FLUID STILL FOAMY OR POWER STEERING PUMP MAKE NOISES.REBLEED THE SYSTEM AND CHECK FLUID LEVEL AND CHECK FOR LEAKS.DONT DRIVE CAR UNTIL YOU START FEELING NORMAL STEERING.IF YOU HAVE TROUBLE DONT DRIVE.HAVE IT TOWED TO THE NEAREST GARAGE.

Autozone ,Chilton manual for about 10.00 has this info

Everyone always gravitates to the suspension but folks, it's 99% sure that it is the EVO. The EVO is the sensor built into the steering column that senses movement of the steering wheel then controls the power steering pump accordingly. When it goes out (which is all too frequently) you get sloppy and loose steering at lower speeds and it does tighten up a bit on the highway at higher speeds. This is the way it is supposed to work but when it fails it's downright scary trying to keep the truck straight on a narrow two lane road!

A very Fast leak Is Simple to Diagnose

1. Start Engine with reservoir Full
2. Have a Helper to sit inside
3. Go under vehicle and look where you suspect leak is
4. Have helper turn steering wheel to
5. RIGHT or LEFT All the way till it stops and hold it there
6. If you see it Pouring out from the Area suspected.
7. That WILL be the HIGH PRESSURE Power searing hose.
8. Under High Demand they have lots of pressure.

The Low side (RETURN will leak ALL the TIME and just Drip unless there is a Large hole in it
Hope I Have Helped

check you power steering fluid level and for any leaks around the unit

Maybe got an air lock/bubble