1990 Lexus Ls 400 Power Steering Pump Making Noise

[Mike Hoop]

I have a 1990 Lexus Ls 400, and when it is cold the pump whines really loud. Any suggestions?

[allgood2001]

I have a 1990 Lexus Ls 400, and when it is cold the pump whines really loud. Any suggestions?

Have your fan belt checked. You can replace it yourself if needed, it's pretty straight forward.

[badboy50]

check the fluid level and any leaks. I had the similar problem before now it is much more obvious that my pump is most likely faulty.

check out the thread: http://us.lexusownersclub.com/forums/index...showtopic=42618.

Good luck man.

[pishta]

I have a 1990 Lexus Ls 400, and when it is cold the pump whines really loud. Any suggestions?

Have your fan belt checked. You can replace it yourself if needed, it's pretty straight forward.

Does it whine or howl? A howl is the classic "turn your wheels and the wolves start singing". That is a loose belt. A whine in my experience is low fluid, cavitating right above the impeller, top it off and you should be OK. There is a pump and rack rebuild kit on craigslist for 10 bucks plus shipping! All the soft parts you need, looks like a bunch of O-rings. Couldnt hurt.

[steve2006]

I have a 1990 Lexus Ls 400, and when it is cold the pump whines really loud. Any suggestions?

Have your fan belt checked. You can replace it yourself if needed, it's pretty straight forward.

Does it whine or howl? A howl is the classic "turn your wheels and the wolves start singing". That is a loose belt. A whine in my experience is low fluid, cavitating right above the impeller, top it off and you should be OK. There is a pump and rack rebuild kit on craigslist for 10 bucks plus shipping! All the soft parts you need, looks like a bunch of O-rings. Couldnt hurt.

Hi,

Sorry for my ignorance but could you provide a link for "craigslist" as doing a PS pump rebuild.

Thanks

[french 1990 lexus ls400]

i had the same problem. Go see my topic on this forum. Good guys answer me to emptying the oil system and turn right and left several times. cause there is lots of air in the system. After i remake the level with dexron and the tomorow morning : the noise has disappear.

[ericw10]

I have a 1990 Lexus Ls 400, and when it is cold the pump whines really loud. Any suggestions?

I just bought a 1990 LS400 and was going through the fluids. I changed the P/S ATF to a synthetic Mobil1 Dextron III. Worked fine for several days, but then began to whine only in the morning when cold. After things warm up, it quiets right down. Steering effort seems OK. I don't see any evidence of leaks either. Did I get air in there because I have tried the left to right bit and no help.

Is there a thread on how to "bleed" the hydraulic system of air? I searched but didnt see it.

[RDM]

Bleeding just entails turning the wheel left to right numerous times, while the engine is running. You may even find a short drive doing figure eights will help.

But by changing the fluid to the correct stuff you may have uncovered a problem that was already existing, the ATF is a thinner, lighter fluid so if you had a leak it's more prominent now.

[91LS400Lexus]

Oh how I know that sound!! :)

Mine would do that when I would get low on PS fluid. Fixed that with a new return line. Still had alot of PS issues after that, but after a new (used) rack solenoid and cleaning the PS pump screen (which didnt even look that dirty), the steering started working good again.... took it about 200 miles though.

Now I battle a check engine light. This car loves to keep my blood pressure way up.

[ericw10]

Bleeding just entails turning the wheel left to right numerous times, while the engine is running. You may even find a short drive doing figure eights will help.

But by changing the fluid to the correct stuff you may have uncovered a problem that was already existing, the ATF is a thinner, lighter fluid so if you had a leak it's more prominent now.

That's what I feared, that the new synthetic fluid was now doing its job by cleaning out the accumulated varnish etc and maybe clogged the solonoid and/or reservoir screen. Now its running in high pressure mode all the time, but when things heat up, viscosity drops, pressure reduced and no noise. Guess I will be pulling out a solonoid screen tonight. Oh joy.

No leaks that I can see. I bought a drip pan 3 days ago and have had the car park on it every night and no sign of ATF anywhere...................yet.