1990Lex400

I have a 1990 lexus ls400. Recently the powersteering stops working at idle. It works again when the rpm's are higher under normal driving. It also works at idle when i first start the car because the rpms are higher at start (approx 1000 rpm).

Any ideas? I called the dealer and he said just to test it would be almost 200 dollars. And if it's the computer than another 500 atleast. Thanks for the help.

ChuH

Have you check your power steering fluid level? If it is low then either your power steering pump or hydraulic hose is leaking. Note that you may have to also replace the alternator that sits right below the power steering pump. If leaking the power steering fluid most likely has begun to damage the alternator.

Of all the V8 Lexus I own '92 & '95 SC400 and '95 LS400 I had to replaced the power steering pump and alternator. For the SC400 I replaced my with refurbish pumps for about $300 each. With the LS400 I had them use the Lexus power steering pump seal kit (about $30 but additional 3 hour labor) to refurbish the pump. Also had to replace the hydraulic hose for the power steering.

Chu...

retrodrive

http://www.cureline.net/lex/performance/pspump.txt

GA400

Like retrodrive's link suggests, I used the stop leak stuff on my power steering pump. Fixed it in about two weeks. Trusted Lexus mechanic told me if pump not making groaning noises it was still fine, try stop leak first, then rebuild or replace if necessary. Now I just have to find a way to get the !@#@#! fluid out from underneath the pump and off the black rubber shield underneath the engine!

1990Lex400

My power steering fluid is not leaking. Since the problem first started happening i filled it up with ps fluid and checked the levels. The levels are still up.

Chu: Did you replace the pumps because the ps fluid was leaking or because of some other reason?

Thanks for any other thoughts, replies.

GA400

Okay, so the fluid is not the issue. How about the drive belt that powers the pump (and damn near every other accesory for that matter)? Is the tension good (shouldn't flex much when you push it with your finger). Is the belt good (no dry cracking)?

ChuH

1990Lex400:

In all three case the pump seal were leaking. Only the LS400 had a bad hydraulic hose connector also. Mechanic originally tried to cut the connector off and installed a new connector. Because there was a loss of length to the hose due to the cut it cause a slight bending and pinching to the hose. The result was causing additional load to the pump. If at idle you turned the steering wheel it would cause the Engine Light to lit up. End result was to replace it with a new hose.

Replacing the pump or using the reseal kit is the most common problem with the SC400 and LS400. If possible check to see if there is any record of your LS ever had it's pump replaced or repaired.

Chu...

ChuH

1990Lex400:

One more note. In all three cases the Lexus mechanic also inform me that another cause of problem would be the steering rack. This would be quite expensive to replace. Due to the age of your LS and that you do not have any visible leak there may be some sort of blockage or reduced hydraulic pressure at low rpm.

To clarify the repair history of the LS400. Did the reseal kit for the pump. Then a few months later found a small leak on the hose connector near the pump. Dealer tried to save money and cut and install a new hose connector. Immediately at idle when you turn the steering wheel the engine light lits. Dealer then replaced the ECU but it did not fix the problem. End up replacing the hydraulic hose and all the problem disappeared. Before they replaced the hose they said the next possible problem would be the steering rack.

When you turn your steering wheel at idle does it make any sound?

Chu...

1990Lex400

When I turn the steering wheel at idle it is very difficult (not impossible by any means but requires considerably more force than when working properly). There is also a groan noise. Maybe a loud hum depending on how you describe it.


PS I want to thank you for your help to all those who have replied.

GA400

Based on what the Lexus mechanic told me, the groan means it needs to be rebuilt or replaced. One note - Auto Zone here has the pump for $104 + 40 core charge, lifetime warranty, installation should run 2-3 hours labor - doesn't have to be at the Lexus dealer - pretty straightforward. Lexus dealer here wanted about $850 to do it. Like Chuh said, it may be the steering rack. I suspect that is pricey. Any local mechanics you trust? You could always take it to the Lexus dealer for an estimate, then make up your mind.

Good luck, Dude.


Rich