Blog Comments

Thank you for the kind message, Clive.
Hope it will be useful for some of the owners.

Wishing you and your family a Merry Christmas and a Happy New Year.


Hi, Bruno.
99% of the time, the ABS is triggered under panic brake situation or while braking over the rough road surface for the street driving condition so not a bad idea at all for upgrading to the latest ABS even the hardware/software setup (targeted slip rate) of 00+ ABS is done for the later spec chassis setup including (but not limited to) calliper/disc/suspension/weight distribution/etc (and the brake booster setting as well for the case of NSX-R).


At the end of the day, it’s you - the driver - who makes the chassis to work for yourself so knowing the characteristic of your tyre, brake, ABS, etc will assist you in driving the NSX.
You just need to adapt/change yourself if something doesn't work for you or if you can't make it working for you.
Several professional drivers in NSX, GT-R, etc showed me how to brake as well as how to control the chassis and even with completely wrong alignment, poor/cheap tyres, etc, they will adapt themselves to get the most out of the available package.
As I wrote somewhere on here, discussing about static alignment, which tyre is recommended based on tyre category, etc means almost nothing once you have experienced this stage.

Regarding the classic ABS....
I was scared and concerned about the potential issue/risk with the classic ABS that I have no regret in making quick decision for upgrading to the latest ABS despite the expensive parts cost.

(If you buy the latest ABS modulator from Japan, it’s still reasonable and nothing like the RRP of US Acura or HUK. I know some of the US vendors are buying it through their contacts in Japan.)

I tested the scary/risk situation on the wet skid pad and also down slope covered by snow so it’s based on my real experience plus the same feedback from many owners in Japan who experienced the same and some of them were unfortunate damaging their NSX on the public road and on track.

For my limited driving skill, I would rather have my ABS working than hitting something and damaging the body panel as the repair cost would easily exceed the cost of ABS upgrade.

The issue with the classic ABS is that it’s a high pressure standby system based on the fluid (with limited amount) stored in the accumulator with slow to respond brain power of the ancient controller.

I must say it was the first 4 wheel ABS for Honda so inevitable, unfortunately.

Even with the healthy classic ABS, there is limited amount of high pressure fluid held inside the accumulator.
The loss of high pressure fluid after activating the ABS won’t be re-charged again until the controller sends out the ON signal to the ABS pump based on the simple feedback from the pressure switch.
Therefore, after activating the ABS, you never know whether you have enough high pressure fluid left inside the accumulator or not for the next braking situation that triggers the ABS.

The next time when you hit the brake pedal and you had to keep braking for prolonged period or the surface was at low mu (friction coefficient), you will lose the high pressure fluid quickly while still under braking and the ABS pump will kick in.

However, the threshold pressure (pressure switch activation) for triggering the ABS pump is too low and the pump itself is so slow that your pedal force will exceed the remaining pressure of the accumulator fluid.
Once this happens, there will be no more ‘kick back’ at the brake pedal and thus, no more ABS resulting in locking up the wheels for a long time.
When this happens, you feel as if the brake pedal got sunk to the floor because suddenly, there was no more kick back by the ABS.

You need to release the brake pedal for a fraction of a second to unlock the wheel and let the ABS pump to re-charge the accumulator but for majority of the drivers, it’s not an easy task to release the brake pedal when you are under braking.

So, unless you are super sensitive to the brake/ABS and chassis behaviour or tracking your NSX regularly, just upgrade it if you can justify the cost by reviewing your annual mileage, how you drive your NSX, the priority and the cost involved if the unfortunate thing happens.

As mentioned, if done properly, the changes are night and day.
Faster reaction time, much more detailed control, no more squeaking ABS pump, no need to ‘exercise’ the system regularly, much lighter, no future worries of leaky/sticky solenoids, etc, etc, etc....


Still, it’s nothing special and by upgrading the ABS on our NSX, it just managed to get to the ordinary level of today’s ABS standard…..
On the other hand, it tells you how far the classic ABS is behind the standard of ordinary cars on the street these days…..

Kaz

Thanks Kaz - really helpful.

Thanks for sharing this information Kaz!

I would like to ask you if upgrading to the 00+ ABS with 91-96 setup could be a bad idea?

Thanks

Bruno

Well done Kaz.
Very good, clear, sensible advice given in a very easy to understand logical order.
You have obviously answered and advised such a simple question many times over the years as it shows.

Merry Xmas and a prosperous New Year to you and your family.

Clive.

Hi, Roman.
It’s quite easy on NSX apart from the LEV and NSX-T models.
Fairly limited space for accessing the rear bank with that air pump metal pipe in your way…..
Also, targa model is much easier by removing the triangle brace (I know one owner managed to replace IG coils without removing this brace....) and this means that you need to somehow hold the engine cover.
I hate removing the engine cover on targa model because it takes ages aligning it later in order to prevent fogging up of the rear hatch glass.

For disabling the IG, since you are doing the compression check, you would remove the IG coil and spark plugs any way so not much to say.
The ignitor module won’t be damaged by the lack of target module connected unlike some of the circuit designs.
For other conditions that you don’t need to take the IG coils or spark plugs out, you can disable the IG by disconnecting the busbar connector on top of the trans or just disconnect the ignitor.

For the INJ, just disconnect the INJ resistor or the busbar connector depending on the year model. The spec of the INJ changed over the years.
The connector for the INJ resistor or the busbar is mounted at the exactly the same location.
It’s on the bracket located at the Right side vertical section of the engine bay.
Just disconnect it and no more INJ.


I own the copyright of the original photos so in theory, I can use them freely but you won’t see some of the photos that contain the security related items, VIN, reg. no., etc.
For the same reason, I treat some of the data as private matter and one of them is the compression data.
Just my own policy since Day1 and as it’s my policy to treat everyone in the same way, I just kept doing it.

Kaz

Hi Kaz,

I used to do compression checks every year for my s2000. It's a bit easier than on NSX too. How do you kill the fuel and spark delivery? Also if you don't mind sharing what's the reasoning behind not exposing customer's compressing test results?

--Roman

Hi Kaz,

Thanks for sharing. I noticed you do bleed it per service manual after vacuum fill. I was curious about priming mostly because it would let less air in hence less bleeding. This is my first time using vacuum fill. And first time changing coolant in NSX.

Can you tell more about single vs two stage pumps? Just curious.

Thank you,
Roman

Hi, solidol.

You can use any type of tube/hose that you can find at your local DIY/fish tank/garden/etc stores.
The drain bolt diameter is 12mm so if you can find something with internal diameter just a bit smaller but flexible enough to expand, that will be fine.
If you have header, you may want finding something not too flexible as you will have very tight space attaching the hose to the front bank drain plug.

As I got used to this task and having access to lots and lots of used coolant hoses, I just use the old overflow tube with the tiny clamp from the coolant header tank and just insert it over the tiny drain port of the drain plug using the 90deg angled long plier. I then extend this narrow tube with much wider clear tube that I got from DIY store.
I like this method because quite often, the drain plug is partially blocked with the accumulation of sticky residue inside the coolant and the coolant won’t start draining until you blow low pressure air into the tube. You don’t want to open the drain too much as it will allow the coolant to seep out from the threaded section of the drain plug making mess.

Just make sure to cover up the front header/downpipe with something to prevent the coolant from touching it.
Otherwise, you will get the smell of coolant for long times unless you wash it off thoroughly before starting the engine.

Regarding priming of fill hose…..
It depends on the equipment and method you use.
My equipment is single stage so won’t achieve nearly true vacuum. I also bleed the air in three stages even after using the vacuum fill method so it doesn’t really matter whether I prime the fill hose first or not.

If your equipment uses two stage pump, then best to prime the fill tube because by the time you fill up the system, there is almost no air left and thus, you just need to run the engine long enough and no need going through the air bleeding method as per the workshop manual.

At the Honda factory, they use this system so they don’t need to bleed the air from the cooling system.
Same goes for the brake system.

It’s actually the other way round. There is no time bleeding the air at the assembly line (except for some of the hand build models) so you need to use the equipment that doesn’t require the bleeding process.

Kaz

Hi Kaz,

Thanks for recommendation. Just received new radiator today. I also ordered OEM upper and lower hoses and four new clamps. As well as four mounting rubber bushings. Just to have everything refreshed and tight. I also picked up this kit to try vacuum refill/bleeding for the first time. Do you always prime fill hose?

Also what hose diameter and fitting do you use to connect to F/R engine drain holes? Just want to make it a little less messy.

While I only use rain water for washing the car as I live in hard water area, I just use tap water for rinsing the rad although I have water softener equipped in my house.
You can use plain tap water even if you live in the hard water region for this purpose as you can drain the water really well from the rad any way.
Just give it a good rinse although I have never seen anything left inside.
If the upper and lower coolant hoses are more than several months old, you may want replacing both of them at the same time as the shape of the hose neck is slightly different from the OEM one.
Because of this, you will need to set the hose band/clamp slightly inward (only like 5mm) compared to the OEM position and for this reason, you want to use fresh hoses as the rubber will take set over time and under heat.

Kaz

Hi Kaz, I'm waiting for Koyo radiator to arrive anytime soon too. What do you rinse it with? Just tap water or any special solution? Thanks

Hi, Alan.
If you visit the following link and scroll down to the comment I made on the 09/Nov/15, then you will find the information.

http://www.nsxcb.co.uk/entry.php?165...oyo-Rad-etc-14

Kaz

Hi Kaz, would you mind sharing about the set up and tools required if I want to perform a similar pressure breeding the brake system?

Regards

Alan

For 91 model, the ‘Lot No.’ on the black plastic case would consist of only 4 digits. From certain year models, it started using the 6 digits.

The 91 model CCU board would be dark green colour with all 13 electrolytic aluminium caps in black body.
No chance of surviving until now if it was the original board.

If you have light green coloured circuit board with brown caps, then it’s from the much later model or someone purchased the replacement new board from Honda.
Even with the later spec board, sooner or later, it will start leaking the acid unless you upgrade the caps.
Even the final year model is already 10 years old…..

Some of the parts used on the CCU board are not RoHs compliant that you can no longer get exactly the same parts unless you have access to the remaining stock on the market.
Therefore, once the existing CCU board stock at Honda is gone, that's it.


Kaz

hello kaz

upon inspecting my CCU board, it is light green and all the caps are brown?

is this a late model version?

the actual car is a jdm 91 so its not original

whatever it is, there is zero leakage on the board and it looks brand new (was expecting to see a mess due to the age of the car)

The main cause of the fire or the smoke is the acid leakage from the caps around the warning indicator module circuit behind the actual warning display.
It’s on the rpm gauge circuit board.

Most of the time, the first symptom is that the ‘BRAKE LAMP’ warning stays on despite all brake light bulbs are operating fine with similar OEM spec ones and also even after checking for any corrosion inside the bulb sockets or the female terminals inside the big 20pin grey connector behind the carpet at the forward left section of the boot.

To be 100% sure that it’s the gauge issue triggering the false BRAKE LAMP warning light and not by the wiring, bulb socket, bulb spec, etc, there is a way to disable this warning light by doing something outside of the gauge unit.
This will disable the BRAKE LAMP warning circuit so for safety reason, I’m not going to tell it here but you probably able to find it out from somewhere else.

If you carried out this test at the green connector of the gauge unit and if the BRAKE LAMP warning stays on, then it’s 100% confirmed that the issue is inside the gauge unit and you better act sooner rather than later.

On some cases, when the owner ignored this false BRAKE LAMP warning light, eventually, they started experiencing another warning on the display module such as the door open warning even when both doors were properly shut.

Then, it’s the matter of when and not if for the fire/smoke to appear.


In fact, just recently in Japan, another gauge unit developed smoke from behind the steering wheel.
The owner ignored the false BRAKE LAMP warning and kept driving.
Then recently, while he was driving, he started to see some smoke.
It was not enough to catch fire and just burnt part of the circuit board but still, not comfortable seeing smoke inside the cabin especially while driving.


On NSX Prime, I saw several owners reporting the BRAKE LAMP warning despite the fact that all of the brake light bulbs were fine.
Some of them decided to disable the warning light.
Hope they checked everything mentioned above and confirmed that the warning light was caused by something else and not the leakage from the caps on the gauge circuit board.

Kaz

Kaz has done the boards in my car as a purely precautionary measure. Cheaper to do it before they break. I had the power line upgrade done on my head unit at the same time.

MC

Its massively impressive that you save all those circuit boards!

Do you recommend to take the head unit and the climate control apart for inspection and capacitor replacement even if they still work ok?

I have access to professional soldering gear at work and probably even all the needed parts. Everything still works but I have a slight feeling that some preventative maintenance could save me a lot of headache in the future.

Would be an interesting winter project though.

Cheers,
Bernhard

I have noticed that the illumination on my dash board is poor to the left hand gauges. I can't see the indicators on the dials. Is this lily to be a bulb problem?

as above?
why does it catch fire and what is the fix?