I discovered that my trunk had a TON of water (like 5 inches) after removing the tookkit one day. I had a suspension problem and car was sitting outside the shop waiting for parts.

Of course in Vancouver rain, my car collected the water and somehow ended up with 5 inches of water in the tookkit well.

I had to take out all the carpet and found that the car still collects water when just sitting in the rain and collects ALOT of water when being driven.

Obviously isn't not a hole in the floor of the trunk , or else the water would leak out, but I can't seem to find where it's coming in from. And since i can't find where it's coming from, i can't sand away the rust and repaint. I have to keep a spare towel in trunk to soak water and basically can't really use my trunk because there's no carpet to line it and i dont' want to scratch the paint for fear of more rust!

I feel that even tho the rubber seal seems fine, it might be allowing water in somewhoe. Does anybody else have any ideas on how to detect the leak?

The next step is for me to take out the passenger seat, and open up the vent hole, and peak through there with a flashlight and get a friend to spray water and look for a leak....

Any help would be apprecieated!

 

First eliminate the possibility that the water is coming in from the antenna.
Inspect the rubber seal really carefully to see if it has any breaks in it or if it is cracked or warped.
Can you get a powerful light and put it inside the trunk? Run the cord out the back, bottom and middle of the trunk if you can. (Do this at night in a pitch black garage. Turn on the light and see if you can detect the light. If you see gaps, you have your leak.
If you can't see any light, lay newspapers all inside the trunk. Water the trunk with a garden hose for a few minutes. Check for wet spots.
If neither of these helps you find the leak then: Clean the rubber seal with warm soapy water. Apply silicone grease to all the rubber. You can get this at Honda or any car dealer. All cars have rubber seals and they all need treating. Clean off the underside of the trunk lid where the rubber seals up against it.

You have now done pretty much all you can do at home. If this doesn't fix the leak, then you need to go to a professional.

 

Another possible source is a small vent flap behand the rear of the bumper. Don't know what it is there for but they have leaked in that past and many folks have siliconed them up. Do a search for trunk leak. I'm with XV thought the most common cause is not lubing the cars seals. Honda has a special lubricant that works in all temperatures ....Shin-itzu grease I believe it is called. Start with this and then check the vent if you still have moisture.

Utah

 

Has any work been done to the ragtop? Check those joints for leaks with the newspaper, as X mentioned.

As well, water drains to the left and right side of the vert. Check the rain rails, page 20-39, the drain tank and lower drain hoses, page 20-52.
Well, failures in that area would show up in the forward part of the cabin.


Good Luck.

 

Another few thing on the list to check is the tailamp gaskets. H20 can leak past to foam gaskets and seep into the trunk.

Has the car ever had any severe accident damage? Ity fairly common for cars that have body damage to not have all the welded seams sealed and leak.

 

Was the car parked on an incline (with one side being higher than the other)?