Hey all,
on my 93, 3.o,4x4, auto truck,the steering is hard to steer at a stopped idle..but is fine while its rolling...on the fsm online,,theres a progressive power steering..i dont have that..its the regular power steering unit page (sr-75)..now i've done the trouble shooting:the bleeding, the pitman arm,relay rod..all that is fine..what was strange was that it said the speed sensor plays a part too..mine was bad..but i jus changed it..still has hard steering at a stopped position...the only thing i can think of outside changing the whole pump is:

The flow control valve, does this sound like the culprit?..if so ..rebuild or replace

or the air control valve..how can this be checked to see if it is working properly
OH..I REPLACED THE O-RING ON THE PUMP SHAFT AND THE SCREEN IS CLEAN ALSO INSIDE THE RESIVIOR

thanks

 

sounds like your on the right track, im not familiar with toyota systems, but i am with gm stuff and they use a variable type steerng system also. If it doesnt whine or act low on fluid or not blead properly it almost has to be a pressure sensor or the air/vacuum valve. Good luck