Power Steering Problem

[Foosblood24]

I'm having an issue where my power steering is "bouncing" from one setting to the other. It seems there is one loose setting for parking lot maneuvering, and another stiffer setting for driving on the road. We have already changed out the cluster so it's probably not the speedometer sensor.

What I would like to know, is there a way to bypass all this and leave it on one setting or the other? Preferably the stiffer setting as it's not that bad to steer in a parking lot, a little muscle involved but not like losing power steering altogether.

[DCaff300ZX]

There is no "setting" to the powqer steering that I am aware of...the system is very basic, a hydraulic system where the fluid movement causes the steering to be easier to move. Leaks and low fluid or plain old worn out (VERY common) rack or even sometimes suspension issues affecting the geometry such as the FUCAS are the main culprits for notchy, slack, or overly sensitive steering with the Z32.
I suspect your FUCAS are FUCA'd...haha. But seriously, jack one front wheel and grasp the edges of the tires at 2 and 7 as on a clock, and try twisting and lifting at the same time, feeling for anything to start making clunking noises up and towards the back of the wheel wells...the FUCAS. Common, and they also show their failure with excessive camber when on the ground and insides of the tires worn more than the rest, but no toe-in problem.

[Foosblood24]

Yea the rack and hoses are all new and installed at Z1. The guys even put in a new cluster to see if the speedo sensor had something to do with it and still it's still doing the same thing. It'll be loose one minute and then stiff the next.

I did find one writeup that says the HICUS sends a signal that regulates the voltage going to the solenoid on the rack where the full 12 volts is "parking lot loose" and it drops down in voltage the faster you go for a stiffer feel. The writeup talks about bypassing the system and using a DC/DC converter and setting it to a specific voltage for a permanent stiffness (he recommends 8 volts as a happy medium)

https://www.sau.com.au/forums/topic/453 ... nce-level/

[DCaff300ZX]

Hey Foosblood, thanks for posting that writeup!
Great info, I learned something new and saved this to my collection of mods and anyone else should, too.
Seems to me that unless you have and deleted HICAS, you shouldn't have the issue so this problem seems strange in an NA...post up if/when you find a solution!

[Foosblood24]

Will do DCaff. Please keep in mind the writeup is for a Skyline and not the Z32. The grey plug in his pictorial is not there on the Z. With that in mind, I am going to try and single out the power line from the ground on the solenoid itself and put the DC/DC volt selector to that. This should (in theory) bypass whatever voltage signal is being sent to the solenoid and replace it with the selector I wire to it. I'll snap some pics so as to record it for anyone who wants to see.