No Power Steering On My 100 !!

[SINCITY100]

O.K..... At first I wrote off this "issue" as being a design flaw, but now its driving me nuts !!
From a stand still, or very low speed (under 5mph) with the front wheels cranked 2/3 or more left or right, and I gun the motor (especially on low traction surfaces), The power steering is virtually non-existant !! It takes a huge effort to turn the wheels and control the vehicle, (in fact the other day I pulled out of a car wash and onto the street with some heavy gas pedal and I was unable to correct the slight slide that occured when I gassed it, causing my 100 to go straight for the curb !!
This has happened more than once, but only under these fairly specific conditions....could it possibly be the VSC kicking in trying to correct a "perceived out of control situation?
I dont know how many of you folks have had a 100 sideways, but without power assist, it is downright scary !!
I appreciate any comments !!
BTW..Mine is a 2000 with the center diff unlocked (of course)

 

[Jukelemon]

Sin:

There is a lot of stress you are placing on the power steering if you are gunning the engine when your wheels are turned that way. I know on mine that once you get to the far ends of the turning radius, the power steering seems to weaken and I can imagine if one is gunning the engine, it would seem like the power steering has failed i.e. a lot of torque being applied in the direction of ahead when your wheels are in the direction of left/right. Just a thought.

 

[SINCITY100]

Sounds like a good possibility.....I realize that full-time 4x4 systems act different than a rear drive vehicle, but it seems as though this (lack of assist) could be very dangerous if caught off guard.

 

[Jukelemon]

I would agree and I think you were on it when saying it was a design flaw.

 

[e9999]

our 03 has some sort of progressive power steering mode that makes it more or less assisted depending on vehicle speed. Could there be something wrong with yours if you have the same feature?

 

[SINCITY100]

I suppose it is possible that there is a problem with the variable rate steering system, but considering the factors (happens under same conditions) I am leaning towards a 'BINDING' situation within the drivetrain due to the full-time 4x4 set-up....I actually work (19 years) for Toyota and no-one has ever brought up this issue before....

 

[98LXand99LC]

.....I actually work (19 years) for Toyota....

So, you gonna tell???? What do you do?

 

[Jukelemon]

sin:

I am not sure that you and I are talking about the same issue/feel. My experience does not feel like a binding as much as a signifcant loss of wheel control/support when you get to that far left/right segment of turning radius. The increase in needed torque to turn the wheel after you gun the vehicle would be caused from lack of positive torque being applied to the steering system so the wheel feels, for lack of better words, in place rather than wondering. In other words, my vehicle will sometimes feel like it has TOO much PS influence on the steering i.e. loose. This happens as well when you place a very strong (for lack of better words) PS system on a 40 with smaller tires. There is just no positive feedback (in terms of road feel) from the system to the driver. That is what I experience.

 

[SINCITY100]

sin:

I am not sure that you and I are talking about the same issue/feel. My experience does not feel like a binding as much as a signifcant loss of wheel control/support when you get to that far left/right segment of turning radius. The increase in needed torque to turn the wheel after you gun the vehicle would be caused from lack of positive torque being applied to the steering system so the wheel feels, for lack of better words, in place rather than wondering. In other words, my vehicle will sometimes feel like it has TOO much PS influence on the steering i.e. loose. This happens as well when you place a very strong (for lack of better words) PS system on a 40 with smaller tires. There is just no positive feedback (in terms of road feel) from the system to the driver. That is what I experience.

I understand the physics of what you are describing, but the steering angle does not seem to be excwssive enough to cause such a noticeable loss of steering....I am talking SERIOUS effort to straighten the steering wheel (it reminds me of a locked front diff and trying to turn the wheel hard!)

I have run this scenario by our (Toyota) service guys, and they seem stumped...we are going to put "er" up in the air and take a look for anything strange this afternoon....

I am very surprised that no-one has experienced this on a 100 (o.k., maybe Ii am a little bit of an aggressive driver) , but we (@ TOYOTA) seem to think it (steering effort) is more excessive than normal...
I will post back on this if we find anything

PS...U guys are great in here !!

 

[Jukelemon]

Ah, that is serious effort then. Nothing like mine. I am not sure how the trac control works on the newer LC's but I wonder if the TC is sending most of the torque to your front wheels during this type of experience creating an experience like a locked front dif on pavement. ????

 

[SINCITY100]

I think you might have hit on something, The rear wheels on a slippery surface when the vehicle is anything but "straight ahead" would certainly be the first to break free, and without the center diff locked, this might be amplified because the power has to go somewhere to gain grip......thus the biased front end would be stuggling between (both front tires) to retain traction and , hmm...maybe pumping the front brakes harder on one side than the other.....much more on the inside wheel, which would have less traction by far than the outside (of the turn) wheel because of the weight and inertia shifting to the outer tire which would be under load with the most grip......this make some sense....

hey...THANKS ! I am going to experiment and see if this is the case....if nothing else, it gives me an excuse to Thrash around the wet streets (uh, I mean the deserts) of Vegas..lol

 

[lexs470]

interesting post.
I've been experiencing heavy steering with increased effort to steer even under normal driving mode after i've corrected the pressure to 29/32 from what it was before: 34/34.
I would be curious to know what could be causing this.
has a new power steering pump so don't think that could be the issue...

 

[ShottsUZJ100]

Rule out VSC. If it activated you'd hear it working and also hear the audible beep beep beep.