Interior Water Leak

[AR]

How are the door membranes?

[Lankstarr]

How are the door membranes?

I've only ever had the driver's side door card off and it's fine; could probably be more watertight but not by much. I'd like to find the drain first and check that out, if it doesn;t help door cards can be next weekend!

L*

[Kaz-kzukNA1]

Hi, Luke.

Not sure your condensation issue is caused by the water trapped inside the evaporator plastic case but following information will help you for diagnosing the cause.

If you want to have a good look at the drain hose of the A/C evaporator, you need to first remove the passenger side carpet covering the foot bass speaker area. Then, you will see silver flat metal plate protecting the plastic foot bass speaker box. If you remove this metal plate and look across the right shoulder of the speaker box (you don’t need to remove this) towards the centre of the car, you will see yellow SRS harness running vertically along the sloped section of the body panel.

There, you will see big white plastic case and the drain hose is attached to the forward left corner of this plastic box. The photos that Sudesh uploaded in post #4 of this thread will provide you with some idea.

The key points are the vertical yellow harness, sloped body panel, centre of the body, quite forward than where you think.

If your passenger side carpet and floor were not wet, I don’t think you’ll get much information by inspecting this drain hose. It’s short, angled and not that soft. You should see white or yellow check mark from the factory on the hose so if it is plugged in tightly to the white case, then leave it without removing it.

If you can put your NSX on the stand or on the lift, please look at the area behind the steering rack between centre and passenger area. You should see a small and very short black hose outlet sticking out at the sloped section of the body panel. This is where the moisture from the evaporator is drained.
If you have access to the compressed air, you can use short burst of air to clear up the blocked drain hole at the base of the evaporator case as a temporally measure.

The main issue is the debris getting inside the evaporator plastic case. Unfortunately, none of our NSX models were equipped with any sorts of pollen/air filter at the entrance of blower motor. If you use your A/C or Heater in ‘Fresh’ mode and not in ‘Re-Circ’, then regardless of temperature setup, A/C on-off, Vent mode, etc, the air from outside will first directed to the evaporator including any leaves, insects, dust, fume and so on.

Eventually, it will build up on the surface of evaporator fins or simply drops to the bottom of the evaporator case where the drain hole exists. The debris will simply block the drain hole but sometimes, with the moisture, heat and lots of debris (such as leaves), it will form a nice compost and blocking the drain hole.

Under this condition, you’ll see mould at the surface of the evaporator fin. This is why you get bad smell from time to time when you operate the A/C.

You don't want to know what kind of cabin air you are breathing while you are inside the car....

This is one of the reason why I recommend owner to wash the evaporator once a year.
Some of the photos that you can find from the post of my Health Check Service.


The DIY filter that I made for some of the owners. This is the one removed from my NSX a while ago and the clean evaporator after being washed.



The other thing to check is the gas level of your A/C system.
Around this time of the year, you can easily get moisture inside the cabin.

The capacity of our A/C system is huge for the small NSX cabin size so if your A/C is working fine and the drain hole is not blocked, then you should be able to clear the condensation in a short time.

Please look at the check window at the top of the A/C receiver. It’s next to the washer tank blue cap just in front of the radiator and located almost at the centre.

If you see lots of bubble or no fluid movement, there is not enough gas in the system and thus, your A/C is not removing the moisture from the air.

Hope you'll enjoy your next weekend....

Regards,
Kaz