Jump to content

Recommended Posts

Posted

I took the LS 400 (91 model) for a 400km round trip on the weekend. As you all know, its a great touring car that swallowed the kilometers effortlessly, with cruise control set on the highway. The ride over rough roads is superb and the auto transmission is seemless.

Just about the only issue I noticed was that during a constant radius turn, the steering wheel wants to turn back to the neutral or staight ahead position. So the power steering tends to give a little nudge to the opposite direction to the turn. Is this normal on all LS400's?

Its a little annoying, but I can live with it.


Posted

Your PS fluid could be dirty and therefore clogging the line a little...

There is a PS solenoid screen that can clog and cause this problem and also leaks in the system by increasing the "already" high pressure lines.....

Run a search on PS leaks, PS solenoid, etc.... and you'll get a ton of info...

Posted

I have a 90 LS with 86000 miles and the SAME problem!

I have tried to find an answer to no avail (lexus dealer etc)

I like the above reply and will try that myself (PS Solenoid Screen etc)

Good Luck on fixing and PLEASE let us know what happens if you resolve this and I will do the same.

Continue to enjoy one of the finest vehicles ever designed and built!

Ron Johnson

Posted

Isn't the tendency for a car's steering to "self center" a feature of all cars. Some the older (50's, 60's) cars without power steering I've had took some real muscle to hold the steering wheel in a sweeping turn. My Dad usually just letting the wheel slip though his hands to return to center when driving the manual steering cars of my youth.

A "gentle nudge" sounds pretty normal for a car with power steering. We had both a 90 LS and a 00 LS for about a month last year and the steering effort and feel was not all that much different except the 90's steering seemed a little lighter and transmitted a bit less "road feel" than the 00.

Posted

It is definitely normal for the steering wheel to have a self-centering feel. Whats not normal is the excessive amount of torque of that self-centuring feel. During a turn, you should be able to hold the wheel at the position desired with just one of your index finger on to the wheel spokes. If you are unable to do so, then it means excessive pressure build up in your power steering rack. Have the solenid cleaned will solve the problem.

Posted

99lsguy - I have not checked the power steering pump, other than from the outside to ensure no leaks when purchasing the car. What color should the PS fluid be when fresh?

Ronsadvice - what did you dealer do in an attempt to fix your steering issue? I will have my solenoid cleaned at the next service in another 5000km (approx 3 months away). Is it ok to wait until then?

1990LS400 - yes the power steering should return the steering wheel to the straight ahead position, when I let go of the wheel. But it should not try to correct the steering angle to the stariaght ahead position while holding the turn. My Ford does not do that and neither does my Z, but both will straighten when I release the steering wheel once the turn has been negotiated.

Flanker271 - I can steer it with just an index finger and the torque build up is minimal, but enough for me to notice. I wasn't sure if this artificial steering feel while turning was an idiosincrecy of the LS or something wrong with my steering - hence my post.

Posted

original toyota Dex III fluid actually looks clearish / brownish ...like motor oil. Any flushes since the factory would probably be reddish as is most Dex III nowadays.....

Posted

If you look under your car near the stearing gear you will notice a gas charged shock absorber mounted horizontally. It may be that, like all shocks, the valving in this one has failed and is having the effect you describe.

I removed mine right after I bought the car new in 91 so I would get more road "feel".

Posted
99lsguy - I have not checked the power steering pump, other than from the outside to ensure no leaks when purchasing the car.  What color should the PS fluid be when fresh?

Ronsadvice - what did you dealer do in an attempt to fix your steering issue?  I will have my solenoid cleaned at the next service in another 5000km (approx 3 months away).  Is it ok to wait until then?

1990LS400 - yes the power steering should return the steering wheel to the straight ahead position, when I let go of the wheel. But it should not try to correct the steering angle to the stariaght ahead position while holding the turn.  My Ford does not do that and neither does my Z, but both will straighten when I release the steering wheel once the turn has been negotiated.

Flanker271 - I can steer it with just an index finger and the torque build up is minimal, but enough for me to notice.  I wasn't sure if this artificial steering feel while turning was an idiosincrecy of the LS or something wrong with my steering - hence my post.

Posted
99lsguy - I have not checked the power steering pump, other than from the outside to ensure no leaks when purchasing the car.  What color should the PS fluid be when fresh?

Ronsadvice - what did you dealer do in an attempt to fix your steering issue?  I will have my solenoid cleaned at the next service in another 5000km (approx 3 months away).  Is it ok to wait until then?

1990LS400 - yes the power steering should return the steering wheel to the straight ahead position, when I let go of the wheel. But it should not try to correct the steering angle to the stariaght ahead position while holding the turn.  My Ford does not do that and neither does my Z, but both will straighten when I release the steering wheel once the turn has been negotiated.

Flanker271 - I can steer it with just an index finger and the torque build up is minimal, but enough for me to notice.  I wasn't sure if this artificial steering feel while turning was an idiosincrecy of the LS or something wrong with my steering - hence my post.

Posted

:pirate: Dealer checked eveything up front and found all to be OK and in-line etc. We even put new tires on the front thinking we had "radial pull."

We drained the PS Pump and lines etc -

Car drives as straight as an arrow but if you want to "steer" it almost has a mind of its own and wants to go straight again!

I am frustrated but am thinking this is just part of the LS?

Still Love My Car!

Ron Johnson

1990 LS400 - 88,000 miles

Posted

99lsguy - checked the power steering fluid - level is correct and color is brownish, similar to oil as you mentioned. I was concerned that the brownish color may not be contaminated fluid as my transmission fluid is red and from reading the owner manual, the power steering fluid and transmission fluid are one and the same Dex II. So I guess no flushes in 13 years OMG!!!!!

wwest - I'm not keen on removing this shock, but I'll ask my mechanic to check it for me next service.

ronsadvice - Your LS is probably within spec if the dealer cannot improve the feel of centre. I also initially thought that this was inherent steering feel of the LS. Happy to live with it if it cannot be cheaply corrected though as my pull is very minor.

Posted

One thing you are all overlooking is the fact that these cars have positraction . Posi always tends to drive cars straight ahead, that is what it does best. This is a typical characteristic I have noticed when driving any car with posi.

If you want to one finger it through the corners, a car with limited slip is not for you.

Posted

The LS400 has NEVER had positraction nor an LSD. The early ones had Trac as an option but all that would do is apply the brakes to both rear wheels simultaneously to prevent wheelspin and it would also instantly dethrottle the engine at the first instant of wheelspin.

Posted

Power steering rack is the problem. The PPS solenoid is failing. This causes pressure entering the rack to jump up and down and create a steer ahead feel. Buy a new rack.

Posted

Thanks mehullica - I'll get a replacement power steering rack when the pressure builds more and the steering starts to really annoy me.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...

Forums


News


Membership


  • Unread Content
  • Members Gallery