So, I still want to try to seal (caulk or silicon) all 4 sides of my C100 connector. The C100 is in the picture above (in post #26 where I errantly called it a "fusebox") that has silicon on the top edge.

Even after I siliconed the top edge of the C100 where it meets the firewall, water drains down around the sides of it, and gets in through the side or bottom edge of where the C100 passes through the firewall.

My problem is that I can't get my fingers or anything else squeezed and bent in around the C100 to reach the lower sides and the underneath edge. BUT, if I could remove the engine side of that C100 connector (the front end where all the wires hang out), then maybe I could reach around all the edges to seal them up!?

I've been told there's a 1/4" bolt deep in the middle of that C100, but I can't get a driver and extension to squeeze in between all those wires and the wheel well they're crammed up against. Anybody have any tips how to do so?

OR does that C100 unplug on the engine side? If so, how?! I've tried pulling it out and it won't budge! Any tools/techniques I could use, or should I not even try that?!

Finally, am I barking up the wrong tree? Should I be focused on finding a way to keep water completely out of the engine compartment so it doesn't make its way over to the firewall to drain down on the C100? If so, HOW!?

Thanks in advance!

 

lots of posts on how to do it right,mine and previous guys who guided me till i learned. search, go back a few months.
working inside is a waste of time

 

But remember, I've ABSOLUTELY determined that water is coming in through the firewall where the C100 passes through. It MAY also be coming in as you've described in previous posts, nujeepguy, and I appreciate all that, but I can get to those next.
As for now, I definitely want to address the C100 leak, which I know for sure exists. I'll have to do that even if I do what you've spoken about.

SO, again forum community, I'm wondering how to solve the C100 leak through my firewall.
Anyone got anything on this? (more description of my situation, efforts and difficulties in my previous posts).

 

You already got some sealant on the top gap, so it may make what I'm about to suggest a little harder..but..

At hardware stores, and online they sell stick/rope/tape based sealant. It is basically a sticky silicone/poly putty in rope or tape form. It is handy for fishing in/around things were getting to the bottom is difficult. I want to say that when I bought some it was automotive grade rope sealant (3m). But any would probably do. Anyway, you could probably fish it under the connector, then pull it up tight against the bottom gap, and find/make a tool (like a coat hanger) to help make sure it sets in to where you want it, using a mechanic's mirror.

There are lots of different kinds, but here is one example:

Putty Tape / Butyl Tape 1/8" x 1" x 50' Black One 50ft Roll
by GSSI Sealants
Link: http://a.co/9wj4HY2

Here is another that is round:

CRL1401 - CRL 1/4" Round Autoglass Butyl Tape - 1 Roll
by C.R. Laurence
Link: http://a.co/6OBF4LE

 

not sure if you fixed your leak yet but i wrestled with the problem a year ago with a '98 Laredo. there was the issue in the summer with the ac condensation drain needing reaming or condensation soaked the passenger side floor. fixed that only to have the same side flood during rainstorms. i noticed it flooded worse when parked on the street where passenger side was low due to street slope. after pulling the cowl, i found the problem - mentioned in a post above - air intake protrudes through the fire wall. i flooded the area behind the cowl to where the water went over the metal fire wall lip and sure enough, water poured in the passenger side interior. there's foam that keeps that sealed that dry rots over time. very difficult to get to from the inside. the whole dashboard has to come out. just watching the you tube video in FF takes 45 minutes. dealers said they would charge me 8-10 hours of labor to pull it. I got at it from the outside by cutting a flap in the metal in front of the air intake for access. had someone with small hands lube up the entire air intake with 3m 5200 marine grade sealant. flood tested it after and no more leaks. I left the flap (no weld) sealed with some of the 5200 in case I ever have to get at it again. hope this helps. shows the intake with the metal lip. whater gets over the lip and goes to interior
dremmel tool to cut steel. only cut 3 sides to leave a flap
access to intake with both hands.
i just coated the whole thing to insure no more leaks. one tube of 5200 was more than enough
flolded flap back down and sealed for future access.

 

my passenger side has about 3" in it right now... (huge storm this week) gets wet in winter. drys in summer. been doing it for years.. driver side is a bit wet. I've spent time looking before. but who knows where it's coming from. I made a rubber cover / dam thing over the heater system under the hood years back which helped a bit. so water going through the hood gap can't get to the firewall

 

UPDATE: As of Sept. 2018, there's been no more leaking. My solution was that Icrafted a tinfoil shield/roof/rainCover/awning of sorts, sitting right above the C100, taped to the firewall right above the C100, so that any water that comes down the firewall, will be diverted away from the hole where the C100 passes through the firewall (where the water makes it from engine compartment to cabin). Maybe at some point, I'll take some picture(s) to post here.