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the hicas only moves the rear wheels about 1 degree, pretty trippy how much of an effect that has.

i read a thread on hicas ages ago complaining about the hicas on the limit. what happens is when cornering hard at speed the hicas initiates understeer, cos this is safer and way more manageable than the alternative. but once you keep pushing the rear wheels turn as far as they can, and the car oversteers. at which point you go to opposite lock and the car says hey, he moved the steering wheel, and so the back wheels turn in the same direction as the front wheels, but the back wheels are now pointing in the direction of the slide, hence throwing the car into the slide more.

i think i need an example, so you're smaching round a right hander, the back wheels turn right, matching the front wheels, giving you some nice safe, controllable understeer, but you either keep turning, keep pushing or went in too fast and the hicas reached its limit and the rear starts to slide out, so you manage to wimper "OMFG" and steer left hard, and hicas screams "LANE CHANGE" and steers the rear wheels left, but you're already in a slide and now the rear wheels are pointing in the direction of slide, making a super-slide, and calling for the seats to be cleaned.

so, if you're tracking a lot, it's worth dumping the hicas rather than buying upholstery cleaner after every corner. for road, don't bother, that little bit of understeer it gives you is nice and safe and gives a heads up, esp in the rain. a lot of people blame the hicas for their spins, but in truth they probably weren't going fast enough, just too fast for the corner with a boot full of boost.

just some thoughts

  • 4 weeks later...

So i am seriously thinking bout removing the hicas in my R33 GTR.

Between 60km/h and 120km/h, when driving in a straight line. The rear wheels will kick left and right real quick. Sometimes it kickes right then left. It feels as though its doing a quick diagnostic. I have seen the wheels move left and right in diagnostic mode on my car, and it would pretty much be the same, but at speed.

When running diagnostics, it has shown no response from steering wheel sensor. So i may just replace the sensor and see what happens, although i dont think it will fix the real problem.

Now it was only last week I realised these problems started around the time I installed a sub in the boot. I always drive with the stereo at a decent level. I didnt put 2 and 2 together until i was on the highway in the wet, and the back end was kicking out every couple of seconds. This is the worst feeling that i have ever had in a car. I pulled over, turned down the stereo, and then took off trying different speeds to see if that effected anything.

No kicking, no bucking, no nothing. The car went like a dream at any speed. Thinking the worst was over, i cranked the stereo back up and almost instantly, the back end kicked again. I also got to work out what songs made the hicas angrier, LOL.

It will take a while to work out exactly what is wrong with mine, and being cost effective, the lockout bar sounds like the better option.

Any opinions?? HICAS light doesnt come on at all, unless i run a diagnostic, which ran perfectly.(apart from the no response from steering angle sensor).

And yes, i know the easiest fix is to take the sub out!! But for safety sake, I would love to fix it properly.

Sounds like your HICAS computer - located in the boot - is most likely at fault. Could be dry-solder joints affecting connection between components when you're hitting bass, or something more sinister - though I'd doubt it given it's perfect when there's no bass. Given how far away the sensors are (and how simple they are) I would think the HICAS computer is more likely than the sensors.

Anyways, I'd be pulling the HICAS computer out and checking it out. If you see any dry joints, very easy to re-flow them with a soldering iron :bunny:

Check out some of the other HICAS related threads where people re-flow solder (and some have to replace parts from leaking capacitors).

  • 4 weeks later...

any one know who stocks the tierods and tie rod ends for rear steering? its for a r32 GTR,

oh and by the way just jap in sydney sell a double banjo for the hydraulic lines, this save trying to find wat thread to block the holes etc,

its only $40

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