I installed a remanufactured rack and pinion in a 97 LS400. I bled the system by first rotating the pump by hand with the belt off, the system was completely drained of fluid, I had filled the PS reservoir and after hand turning the pump I fill the reservoir again. Installed belt on PS pump. Then I turned the steering wheel lock to lock 50 times with the engine off. Reservoir fluid did not go down. I started the engine to continue bleeding the system. When I turned the steering wheel, it turned back and forth by itself until I stopped the engine. Anyone have an idea what is happening?

 

Last time I saw this, the lines to the rack were swapped. It was on an s13, not an ls400, but I could imagine this would be the issue you're having. Granted, I haven't dug around to see how everything works on the ls400 yet.

 

Why would you turn the wheel with the engine off? That wouldn't remove any air from the system because the pump isn't moving. Not sure what your issue is, i don't see how you could swap the lines on the pump accidentally.

 

It's possible. If these two are switched, it would cause the steering wheel to turn on its own. You have fluid entering the return so while it's trying to send fluid back, it's sending fluid back to where fluid should be pushing. That's why the wheel would turn on its own.

 

I will check that out. Thanks.

 

The service lines at the pinion were swapped. Reversed them and it woks properly. Thank you WhiteUCF for the help.

 

Just pulled a rack and pinion out of a 2006 audi a4. Noticed the two lines had different size banjo bolts and wondered why. Now I know.