pavster

Alright, not really suspension question, but related to handling. I can't stand my GS430's super-light steering; it takes all the fun out of driving; I've test driven all sorts of cars, and I find that I definitely prefer it when steering wheel requires a lot of effort. So, before I ditch the car, I am going to try to modify the existing system to give it more feel. I know the system is variable, therefore, there must be some control mechanism for adjusting the oil pressure. I am guessing it's just a purge valve on the power steering pump -- I see two wires going into it, which might be the purge valve control. Does anyone know if this is in fact correct? I am guessing that the solenoid controlling the purge valve can be controlled either by varying voltage or the duty cycle. The latter is more likely how the ECU controls it.

So. Has anyone attempted anything like this or can assist me in any way possible? My car is a daily driver, so long-term disassembly is out of the question. If you have a picture of the power steering pump that I could examine to infer its operation, or if you know anything at all about the system, please let me know.

I am guessing I am not the only one who prefers a firmer steering feel. If I crack this one, I will be sure to share it with the group.

BTW, my car is a 2002 GS430, so it already has the new steering ECU that supposedly gives it firmer feel. If Toyota considers this firm, I would hate to see what it's like without the new ECU.

Thank you very much!
-Pavel.

rominl

iTrader: (4)

if you really want to do it, it's nothing more than simple. go under the car and you will see where the steering colume ends. there is a hex ****, that's the steering wheel pretensioner. tighten it by 1/8 of a turn and see how you like it. it will be a lot tighter already.

i would suggest doing it too much coz' you will start loosing power steering. but it goes make steering tight

pavster

Thanks for the advice, but I've already done that; I should have mentioned it in the original post. Yes, it makes the steering tighter, but it also makes it feel more detached from the road, like a computer joystick. What I am looking for is intense desire of the steering wheel to center itself during a turn. Good examples are: BMW 330i Sport, Mazda Miata, Saab 9-3.

-pavel.

DASHOCKER

iTrader: (2)

Mine is not loose at all, and I am familiar with the Toyota steering. Feels firm and nice.

pavster

Agreed, it's tight for a Toyota, especially with the tightened pre-tentioner as well as mild suspension mods, but it's nowhere near what a BMW or a Mazda feels like. The only reason I am looking to do this is that I love the car; otherwise I'd be driving something different already.

Speaking of Toyota steering feel, I took an MR2 Spyder for a spin last weekend. It has a very similar steering feel to my GS. So I think Toyotas just always come with this sort of steering. Prior to the Lex I had a Miata and my wife's car is a SAAB, which both require a lot more effort to turn the wheel and once turned, the wheel really wants to come back to center; you would not be able to hold it with one finger without experiencing major pain. But with this brutality comes great road feel, such that even my wife's floaty wobbly SAAB is more fun to steer than my Lex.

Soo, back to the topic. I know that there is absolutely nothing wrong with my car's steering -- it's exactly the way Toyota intended. But it is not how I like it, so I will try to change it. Just like some people add turbos or aftermarket torque converters, I just want my car to feel the way I want. Haha; it sounds so selfish.

I've heard of people doing this in Japan. My first attempt will be to just disconnect any electrical connections to the power steering pump and see what its fallback mode is. I might just get lucky and it will get heavy all the time. Or it might be light all the time. From then on, I'll have to do some electronic hacking to get it to feel the way I want. My concern is that the ECU will detect that I am messing with it and do something dumb, but I guess I will have to deal with that as it comes.


-pavel.

rominl

iTrader: (4)

haha i know what kind of feeling you asking for then, but unfortunately, i am not sure how youcan get that maybe you need to get a bimmer instead

pavster

Yup, Bimmer is certainly an option at this point... but, I haven't yet lost all hope in the big Lex.

-pavel

pavster

Alright, here is an update for anyone who might be interested.

I disconnected the wire harness that's on the left side of the power steering pump, when looking from the front. The difference is exactly what I was looking for. The steering is nice and heavy at low speeds -- I can really feel the load on the front tires when turning. It's actually a bit too heavy at parking speeds (<5mph), but I can live with that.

It's a very simple mod if you want to try it, and it's trivial to go back to stock -- just plug the wires back in. To my delight, there are no warning lights on the dash when you do this.

My theory for what I've done is I disconnected the pressure regulator for the power steering fluid, causing it to always have the lowest pressure. This equates to the same as before feel at highway speed, but much heavier steering at low speed.

Does anyone know of a quicker ratio steering rack that would fit the GS?

-pavel.

TexasGS

Can you take a picture of where this wire is? Heck, where is the power steering pump?

GSquicksilver

dude, have you tried to put a strut bar on the car? i did that and it sure tightened up my steering wheel a bit firmer. how about the l-tuned steering ECU?

rominl

iTrader: (4)

hey congrats man, i guess that's a really good way to kinda "take away" the whole powersteering

Kbueno

Yes....Lexus steering=mush. But I expected that for a luxury car. Is the 06 GS the same?

pavster

I'll take some pics soon -- it's (sort of) winter here, and I don't feel like working on the car when it's freezing out. If you are looking at the engine from the front, on the left you will see the airbox. Right next to it, a little down, is the power steering pump. There is a wire harness that plugs into it with a blue connector. That's the one. You do have to remove the airbox to get to it.

-pavel.

pavster

I haven't tried the strut bar. To be honest, I am seriously considering trading the car for a bimmer, and this is my last ditch effort to make it feel the way I want. If I like this (and I do so far), I will do a bunch of other things -- bushings, strut bar, braces.

I just couldn't stand the stock steering feel that required no effort at all to turn and provided no feedback at all on most roads, and yet at the same time, on certain rutted roads, the car would not go straight and the steering wheel wanted to rip my fingers off.

It's definitely better now, but I need to see how it feels with the summer tires (running snows on 16" rims right now).

As a 2002, I believe my car already has the upgraded steering ECU.

-pavel.

pavster

The GS is marketed as a GT or a sports luxury car, so I expected the steering to be a bit more responsive and alive. For me the contrast coming from a heavily modded Miata into a GS was too much to be able to discern the inadequacies of the GS steering during my test drives; only now that I've spent some time with it, do I understand what it's missing.

Reading the 06 GS reviews, sounds like it's got the same issues. Slightly firmer suspension, but the same otherwise. I haven't driven it though.

-pavel.