I have a 95 ls-400 the power steering pump was leaking so i replaced that. After a couple of weeks i went to turn in to a parking lot and there was no power steering. Put another pump on and it did the same thing. I cleaned the E.V.O solinoid, No help, So i took it to the toyota shop and they said the whole rack and pinon sys. needs replaced. So we replaced the whole sys. with evo valve. Still does the same thing, Bleed the sys. for 40 minutes no help. Any suggestions???????