Sorry I was going to put this in the maintenance forum, but figured the LS guys would know more about our cars.

Anyhow here is the problem. Last year (about 6 months ago) I replaced my P/S pump (reman)along with the lines on my 1990 LS400. It was making a loud noise after the install. I was told to drive it for a week and when parked just turn the wheel lock to lock to get the air out of the lines.

Okay so I did that, but the noise never went away. It would be really loud on cold starts only! After the car has warmed up the noise goes away .

I took my car back to my friend's shop who did the install and replaced the pump with another one and the power steering was totally gone!
And now they installed the 3rd pump hoping that they have sent us a bad pump and guess what?! The thing still makes noise and power steering is gone!

What else could fail in the power steering system of an LS? My friend thinks that there is a solenoid that probably needs to be replaced. Anybody here knows?

Kinda stumped right now guys... HELP!


Cliff Notes:
1. replaced pump and lines
2. makes loud noise ONLY on initial start of the car, when it warms up it dissappears
3. replaced pump...problem still there but now p/s is gone
4. replaced the pump again...problem is still there
5. ....what can cause the p/s pump to make noise during start ups only?

ouch 3 pumps? I'm still on my oem one and its running with no problems at 188k

that really sucks man. i havent heard of the solenoid issue with the p/s

yeah this is the 3rd pump, good thing it is replaced for free!

Anybody?

bump this up!!

Common anybody here know? Somebody has to know or has had the same problem before ...