HICAS - How does it work and what if it doesn't work?

[W4SIM]

Hello

 

Looking at buying a Z, but as i odnt know much about them I thought I would ask questions about things I dont understand before i go and look at it.

 

I know rust is a massive issue, and just about all the ones iv seen have some form of rust or another on them, but another recurring theme seems to be the rear steering not working.

 

Firstly, am i right in assuming that the rear steering is the HICAS system?

 

I've just seen a Z for sale, but on previous MOT's its been noted that the rear steering does not work (although the rear wheels are held in a substantially straight line and this not affect steering). Its also been noted on another MOT of the same car that the "Power steering component(s) has slight seepage from a seal rear steering".

 

Looking around on the forum here it seems that some people are getting rid of the rear steering (Deleting). This leads me to 2 conclusions:-

 

1. It doesn't affect the car too much if the rear steering is not working, the car can still be driven.

 

2. Its more hassle to repair/replace parts of the system to make it work rather than getting rid of it altogether.

 

Would this be about right?

 

Should i be massively worried about this aspect in car im looking at purchasing?

 

And how do i go about deleting this system?

 

Thanks

[Joely P]

How a tester would know whether the HICAS isn’t working I don’t know but I think it’s quite rare for them to fail altogether. The most common fault with the HICAS system is the power steering fluid level sensor which brings on the HICAS light. At this age, many also suffer from worn ball joints on the rear steering rack, causing slight play in the wheels and as that MOT you mentioned points out, you can get leaks from the rack seals.

 

The cost of repairing and maintaining the HICAS system is generally more than the cost of deleting it which is why I think many people choose to get rid. Folk that like to drift theirs would understandably get rid as it would be rather unhelpful and the track enthusiasts generally delete it because they want to be in full control (if that’s the right way of putting it!). Personally, I have kept mine serviceable and find it a useful driver aid.

 

There are different types of lockout methods, some rely on the ball joints to be serviceable. There is also an option to convert the rear subframe to one from a non turbo variant as these didn’t have the HICAS system. This simplifies the back end (and the engine bay if required), it also gives you a faster acceleration due to the gearing but as a trade-off it means you’ll be higher up the rev band at any given speed.

Edited August 26, 2018 by Joely P

[W4SIM]

Thanks Joely, even im not sure how the tester would know that the rear steering is not working, but it is down as an advisory item back in 2014. The leak from the rear is down as an advisory in 2016. Im sure the rear steering is not part of the MOT test, but maybe the tester was an owner or an enthusiast who knew what to look for.

 

This is the car in question:-

 

https://www.ebay.co.uk/itm/NISSAN-300ZX-TWIN-TURBO-/163220557620?_trksid=p2385738.m4383.l4275.c10

 

It looks very nice, but as we know looks can be very deceiving with these cars.

 

Its also a good 5 hour drive away so not exactly something i can just pop over and have a look at. Any Z specialists on the south coast?

 

Thanks

[Funkysi]

Thanks Joely, even im not sure how the tester would know that the rear steering is not working, but it is down as an advisory item back in 2014. The leak from the rear is down as an advisory in 2016. Im sure the rear steering is not part of the MOT test, but maybe the tester was an owner or an enthusiast who knew what to look for.

 

This is the car in question:-

 

https://www.ebay.co.uk/itm/NISSAN-300ZX-TWIN-TURBO-/163220557620?_trksid=p2385738.m4383.l4275.c10

 

It looks very nice, but as we know looks can be very deceiving with these cars.

 

Its also a good 5 hour drive away so not exactly something i can just pop over and have a look at. Any Z specialists on the south coast?

 

Thanks

 

I'd not drive anywhere to see that. It has a very colourful MOT history listing rust as one of the number of advisories or failures repeatedly over the past few years.

 

It's fairly cheap though although you'd spend quite a lot addressing the corrosion on what is essentially an automatic Z. For 500 more I dare say you could find one with a much better underside.

Edited August 26, 2018 by Funkysi

[tomfromthenorth]

White peril indeed.

 

Stuff painted red and dump valves :-/ Chip and exhaust... not convinced.

 

HICAS is really quite subtle. I had mine on an on off switch for ages and it is pretty subtle. I drifted mine with it and without it and tracked it with and without it. It is slightly more consistent in all aspects of cornering without it. More of a difference with my NA back end is the gearing and the lightness.

 

Good advice above. They don't tend to fail joints wear out. Some lockout systems retain those joints anyway. I think HICAS would be good for autocross, 40mph sharp turns in quick sucsession. And at high speed 80ish it stops those not really tight but slightly more than a kink corners feeling uncomfortable, it make the car turn more readilly with a lighter feeling nose. imo iirc.

[Funkysi]

White peril indeed.

 

Stuff painted red and dump valves :-/ Chip and exhaust... not convinced.

 

HICAS is really quite subtle. I had mine on an on off switch for ages and it is pretty subtle. I drifted mine with it and without it and tracked it with and without it. It is slightly more consistent in all aspects of cornering without it. More of a difference with my NA back end is the gearing and the lightness.

 

Good advice above. They don't tend to fail joints wear out. Some lockout systems retain those joints anyway. I think HICAS would be good for autocross, 40mph sharp turns in quick sucsession. And at high speed 80ish it stops those not really tight but slightly more than a kink corners feeling uncomfortable, it make the car turn more readilly with a lighter feeling nose. imo iirc.

 

Dump valves make me cringe at the best of times, dump valves on an auto is like a poor comedy act. :lol:

 

Mirror your sentiment re:HICAS. Sometimes the inner seals go and you'll only notice if you take the inner joint boots off.

[Joely P]

White peril indeed. Stuff painted red and dump valves :-/ Chip and exhaust... not convinced.

 

Yeah, a club member has a white one with stuff painted red, like some BBS centre caps and a red Z badge. Bit gash isn’t it!

 

:rofl:

[Funkysi]

Yeah, a club member has a white one with stuff painted red, like some BBS centre caps and a red Z badge. Bit gash isn’t it!

 

:rofl:

 

Think you'll find those printed not painted. :lol:

[AndrewG]

Yeah, a club member has a white one with stuff painted red, like some BBS centre caps and a red Z badge. Bit gash isn’t it!

 

[Guest]

I think we should respect what other members do to their zed!

Not all members share the same reason for zed ownership.

I have a white z!

That they being a member making a comment because they are not purist is a bit unfair!

It's only my opinion.

[Funkysi]

I think we should respect what other members do to their zed!

Not all members share the same reason for zed ownership.

I have a white z!

That they being a member making a comment because they are not purist is a bit unfair!

It's only my opinion.

 

Joel is on nightshift again, I wouldn't pay any attention to him. :lol:

[tomfromthenorth]

I didn't mean to cause offence and Joely was having a tounge in cheek pop at funky Si.

 

My comment was more that I'm often dubious when I see an advert for any JDM performance car and some of the specifically mentioned selling points are not what I'd be pushing if I were selling.

 

My reference to white was that his top line is "White Perll" My first skim read I thought he was saying "I have here for you, the White Peril!" :lol:

 

I love white JDM cars. White NSX, dream car!

Edited August 26, 2018 by tomfromthenorth

[RichardS]

PMSL at Joel and Si.....:lol:

 

But with regards the HICAS, as said above, the common MOT failure or advisory is down to worn rear steering joints. It's an easy fix, provided nothing else is wrong with the HICAS. Thing is, with the rarity of these cars now, many MOT testers won't actually know how the HICAS works. Easy to confuse it with other RWS systems, where the rear wheels also turn to aid low speed manoeuvring. This does not happen on the 300zx - it's purely a "cornering at speed" aid.

[Guest]

Point taken by all:biggrin:

But we as a club have to support all members, don't we?

[RichardS]

Point taken by all:biggrin:

But we as a club have to support all members, don't we?

 

Yup - dead right Art, we certainly do...…:biggrin:

[Funkysi]

Point taken by all:biggrin:

But we as a club have to support all members, don't we?

 

This is why I suggest avoiding this rusty Z. :)

[Guest]

Si it was other comments I referred to not rust.

We do have members down there that could give it a look over don't we?

[Tutis]

Looking at comments about all zeds that come up for sale there is nothing worth buying. At this rate there will be no new members coming and no new zeds appearing unless imported. Not all of them are that bad and because of a few problems should not be written off it is not some 2003 fiesta. Those cars are rare and need maintenance and they will require money invested. Hicas problem is not much of a problem. 150 quid and you have zcentre/driftworks arms to replace the whole hicas stuff at the back. Thise cars are now approaching 10k value for great examples. Anyone is going to dissagre that this car would not be of good/great standard after investing 3-5k?

[tomfromthenorth]

I had to save mine from rust and dump valves, so yeah it's probably worth saving.

[Funkysi]

Looking at comments about all zeds that come up for sale there is nothing worth buying. At this rate there will be no new members coming and no new zeds appearing unless imported. Not all of them are that bad and because of a few problems should not be written off it is not some 2003 fiesta. Those cars are rare and need maintenance and they will require money invested. Hicas problem is not much of a problem. 150 quid and you have zcentre/driftworks arms to replace the whole hicas stuff at the back. Thise cars are now approaching 10k value for great examples. Anyone is going to dissagre that this car would not be of good/great standard after investing 3-5k?

 

This is true in part however this particular car is an auto. Autos do not generate the same values as manual Z32s, this Z also looks like it's been run on a bit of a shoestring the past 3 years, so expect to do some costly maintenance. Those top value figures you suggest are for very very clean manual examples as you've identified, to get a car to that level requires serious investment and if you have a car which has a considerable amount of advanced corrosion to it, you're not going to see any return on your investment.

 

This was more of a 'be wary, I wouldn't go there' bit of advice and that was not because of a cheap HICAS fix but for the rest. You can still find rust-free auto Z32s in better condition for not much more. £500-£1000 more and you'd get a car you'd probably have £2000 less to pay on for maintenance and rust repair. Just the law of diminishing returns.

 

Whilst Z32 prices continue to rise for high quality examples, we haven't reached that point and we won't for a long time where you can call a Z restoration an 'investment'. It'll still be a money pit as so many are in a poor state still.

 

A good project car with less rust is all I am advising. Quality rust repair is very expensive and time consuming.

Edited August 26, 2018 by Funkysi

[Joely P]

Looking at comments about all zeds that come up for sale there is nothing worth buying. At this rate there will be no new members coming and no new zeds appearing unless imported. Not all of them are that bad and because of a few problems should not be written off it is not some 2003 fiesta. Those cars are rare and need maintenance and they will require money invested. Hicas problem is not much of a problem. 150 quid and you have zcentre/driftworks arms to replace the whole hicas stuff at the back. Thise cars are now approaching 10k value for great examples. Anyone is going to disagree that this car would not be of good/great standard after investing 3-5k?

 

This is a valid point and maybe we are too harsh in the critique of the cars that come up for sale. I’m all up for encouraging buying these cars with the intention for a full restoration but it’s always worth pointing out the general costs of carrying out these repairs to a lasting standard. The reality at this moment in time, is that you can (generally) still buy a tidy car that doesn’t need extensive welding for less than the cost of the above car plus quality restoration. As soon as that balance shifts, I’m sure the buying advice on this type of car will change.

 

With reference to the £10k cars, I would suggest that those cars have had significantly more than the asking price invested into them. Some of the high price tag cars are priced due to the originality but even some of those have been known to have hidden horrors!

 

As you rightly said, we should be encouraging new members to buy these cars but I certainly believe they should be making an informed decision of what they’re buying. I would also argue that advising new members (or any members) to fix these issues by installing poor quality aftermarket arms could actually be counterproductive as the dynamics of the ride quality are now altered and the frequency of parts to be replaced is increased.

 

Please don’t take any of these comments as a dig, I am an enthusiast that would encourage anyone to take the plunge and enjoy owning and driving these cars. However, with so many different paths to take with the upkeep of them and it’s always good to keep a healthy debate of opinions which can help people make an informed decision.

[Gaz 300]

I always tell new members looking for a 300zx to buy the best they can afford and stay away from Z's that need work unless they have the knowledge and space to do work on a project Z. It will work out cheaper to buy an expensive Z than "doing one up" plus you get to enjoy it right away. Long term projects tend to not get finished and after spending a lot of money and time you end up selling it on or breaking it.

 

Average Z's that need minor work but you can still drive is the best middle ground of Z ownership as you fix and use your Z as you go along. But always do professional repairs using oem parts were possible.

 

Rust can now be a Z killer and when I bought my first import 1992 auto TT over 10 years ago it was at a time when rust on imports was very rare but now with Z's being almost 30 years old you need to check the underside, sill's and arches very closely.

[W4SIM]

Gentlemen, a LOT of very good points here and a lot of very good advice as well.

 

Just by looking at the above car from the pictures I would have been very serious about buying it as for me personally, the red calipers etc etc do look decent on a white car. But each to their own I guess. I was also the first to admit that looks can be very deceiving on one of these and waited for you guys to advise me better. As it happens, that car is no longer on ebay, so thats out of the window now anyway.

 

The next question was going to be about wether to repair the HICAS system or delete it, but it seems theres a split on that answer as well. But atleast the option is there to delete it, I dont know if the parts are still available to repair it, or how much that would cost.

[W4SIM]

As has also been pointed out, rust is a very very big issue on these. Although I have not been looking for too long, all the ones I have seen have come up with some kind of a rust history, usually in one of the previous MOT's. Im beginning to think there are no Z32's left in this country that will not have been affected by rust at some point or another, even the imports that are coming to 8 years or over.

 

I wanted to start a fresh thread on this subject, as iv been looking at the "Zed World" website and they seem to be pretty decent in repairing rust and corrosion. And the "Z Centre" seem to sell all the common corroded body parts, so is it really all that bad if its got a bit of rust on it, or had rust in the past.

 

https://zcentre.co.uk/index.php/shop/300zx-z32-body-repair-panels

 

http://www.zedworld.co.uk/wizzai.html

[Funkysi]

Im beginning to think there are no Z32's left in this country that will not have been affected by rust at some point or another, even the imports that are coming to 8 years or over.

 

There are, they're mostly owned though as generally ones that are in good rust-free condition have been enthusiast-owned and continue to be.

 

If you can't find what you want in this country, the best bet is to look at a fresh import. The quality of Z32s is going up, but that's generally within enthusiast-circles. Very occasionally one of those will come up for sale.