Complete Pps Failure

[pvsls400]

hey all I am in a situation and cant go any further. to start off i have done tons of searching between here amd CL. First off my 90 ls had a wine in the power steering pump nothing bad or annoying but then i lost power then it comes off and on depending on its mood so i do a flush and clean resivor screen and the pps solenoid screen, Next i meter the sensor and get 7.0 ohms of resistance then i hook the sensor directly to 12v for a few seconds and feel it click. seems to be fine so i put it all back together and it does the same thing great steering accept when you come off the highway to the off ramp and steering gets hard accelerate up and its fine again. So i put a new Pump on and wallah no wine steering is silky smooth for about 10 miles my customer that wants to buy car gets in and takes it for a spin and it acts up again but no wine or anything but no power so i dive it and i have complete failure no power at all so i flush system again thinking some air got in magicly or i just didnt get it all out on the test drive. i go to the tech manual next and it states to replace rack so today i get new rack and waist 4 hrs removing and installing new rack and i think to myself sweet tech manual says 6 hrs to replace so i am ahead of the game here add fluid dextron III i am sure there is no air, fluid is at proper level turn the wheel and nada nothing.I know pump is working because it shot out fluid out the return line in great pressure. Hopefully some one has had the same problems and can give me some advise! my last resort is to fork out 300 for a new solenoid but i just spent 150 on pump and 440 on rack which is not the problem Help Help Help Help Thanks

[j.barleycorn]

When you cleaned the solenoid screen, how did you clean it? Did you remove the reservoir? Did you use the same reservoir on your new pump?

You might want to do a Search Forum (bottom of the main screen) for air control valve or ACV.

You'll find dozens of posts related to power steering woes using this Search method, too.

Given all you have already done, this valve may be your nemesis. Unless, of course, you were unlucky as I was to assume the reservoir screen was as clean as I thought it was. Good luck!

[pvsls400]

When you cleaned the solenoid screen, how did you clean it? Did you remove the reservoir? Did you use the same reservoir on your new pump?

You might want to do a Search Forum (bottom of the main screen) for air control valve or ACV.

You'll find dozens of posts related to power steering woes using this Search method, too.

Given all you have already done, this valve may be your nemesis. Unless, of course, you were unlucky as I was to assume the reservoir screen was as clean as I thought it was. Good luck!

I cleaned solenoid by pulling screen element off solenoid and blew the screen out in reverse with a compressor, Then I put the air fitting inside solenoid the one single hole on the top,hooked uo solenoid to 12v for a second and blew the junk out of the solenoid in reverse also. I used old reservoir but cleaned it very well soaked it in brake cleaner for a few minutes and used compressed air from the bottom and cleaned it that way and flushed it alot with atf from the bottom, put cap on reservoir and shook it like a martini. it seemed very clean. But a new problem has arose i figured it was not the rack no way no how and the bracket on the rack that holds the dampining rod was in the complete wrong area on the new rack so i pulled new rack and for giggles put old rack on started car and still no power at 600 rpm so i rev it up to 1500 rpm and i have steering back so i am thinking a got a cheap half rebuilt pump, im pretty sure the pump is not puting enough pressure at 600 rpm and this is the culprate will find out wednesday. i will pressure check it with my new pressure testing system if it is here wednesday! Thanks for the help i read youre whole post on youre problems and it was very good helped me alot!