Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

After reassembling everything, adjusted the tyre pressure before going out for the test driving session.


The weather forecast was kind of a mixture of everything over the next few days and it would be warm for 2 days but getting cooler over the weekend.


With this in mind, set the tyre pressure to OEM setup of 40/33psi for the Rear/Front and would like the owner to adjust it to his preference depending on the driving/weather conditions.


While the tyre was cold and before going onto the main road, activated the ABS several times.


The pump didn’t kick in after every time when I activated the ABS which was a good news.


However, it did kick in almost every time after the ABS was activated two times.


With a healthy ABS (original spec) under the same test scenario, normally, the pump won’t kick in until after the ABS was activated about three times.


So, it is possible that there is tiny leakage at the solenoid(s) or the accumulator already lost some of its nitrogen gas behind the diaphragm and not being able to hold the pressure longer.


Owner to monitor this carefully and try to activate ABS regularly because with some of the solenoid related issues, activating the ABS will fix them.


The owner has been experiencing long term issue of high pitch noise from around the driver foot area whenever the car was about to stop.


He didn't even need to press the brake pedal and just using the engine brake in low gear was enough to trigger the noise.


The Owner tried to flush the ABS in the past and after that, he noticed that the noise stopped but then came back shortly afterwards.


I asked him to force the ABS to fail by disconnecting one of the solenoid connector and after that, there was no more noise so it was confirmed that the noise was from the ABS possibly from the solenoid.


I was under the impression that the solenoids won't be activated without the brake pedal signal input to the ABS controller so quite surprised with this fact.


Still learning something new on our special car....


During the test driving session, the noise didn’t happen every time when I slowed down to the stopping speed. So, it is an improvement and similar to what the owner noticed after the ABS was flushed.


However, on a few occasions, I did notice the noise and also on one occasion, I felt the brake pedal kick back when I was about to stop just before the speed bump.


Therefore, addition to the ABS, there is a possibility of speed sensor signal quality issue.


Unfortunately, with the original ABS, the brain is not sophisticated enough to pin point which wheel speed sensor is causing the signal quality issue.


Good thing is, the owner has already started working on this by himself and Front Right sensor is already replaced.


He is waiting for the delivery of rest of the sensors so hope he can replace them in the near future.


Will put the car back on the lift again tomorrow for the final check and then wash the car, prepare the service Log file and create the Photo CD.


Almost ready to return this NSX to the owner and next one is already waiting for its turn.



Regards,
Kaz