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Son of a biscuit eater. Torrential downpour last night for about 3 hours. Passenger side is completely dry. Driver's side was sitting in water. It was dark and I couldn't see very well but it appears its leaking somewhere on the driver's side firewall somewhere. It's also possible, ( I read somewhere on this forum I thought) that I am experiencing the seal failure on driver door window somewhere and its leaking water in the floorboard now. Water is always going to take the path of least resistance, I feel these fixes are working and unfortunately revealing other issues. Driver side water again after sealing firewall grommet.
Just letting you know the OEM brake booster hose has the check valve inside. I typically get as many as I can when I hit the JY because is the only type of valve that doesnt require you to cut the line + hoseclamps.
You simply pull the check valve pellet and insert it correctly inside the new hose. You dont have to get the pellet all the way to the middle of the line, just enough for it to enter the hose. This will give you a solid line that works.
As for the leak. Water hose on full starting from the brake booster area. Full blast for 30-60mins while inspecting for leaks.
If that doesnt yield leaks then on another dry day start with full blast by the window area.
Just letting you know the OEM brake booster hose has the check valve inside. I typically get as many as I can when I hit the JY because is the only type of valve that doesnt require you to cut the line + hoseclamps.
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Yeah, I replaced it when I did Z1 lines. Ever since I had a weird pedal and I attributed it to a ****ty 3rd party part. Upon starting the car, sometimes the pedal wouldn't work or you would have to press with all your might then all of a sudden pressure kicks in and pedal acts normal. I have bled and bled and bled and rebled and cycled every which way and would still have the poor pedal upon start. This was just a fix hoping to change the pedal response to see if in fact it was the valve or something coming apart in the brake booster. Damn near fed up chasing this leak.
Upon starting the car, sometimes the pedal wouldn't work or you would have to press with all your might then all of a sudden pressure kicks in and pedal acts normal.
That is a telltale sign that the brake booster is not holding vacuum. Either you either have a vacuum leak, the check valve is stuck, or leaking, or the brake booster is failing internally. The booster is designed to store vacuum pressure to provide brief brake assist with the engine off. If the pedal is hard to press (ie. to start the engine) after the car has been sitting for a brief period of time, then that reserve vacuum is being vented to atmosphere somehow.
Last edited by ILM-NC G37S; 05-08-2023 at 08:16 PM.
Correct. That's what I am thinking as well so I opted for the cheapest "fix" right now, replace the hoses, replace the check valve, replace the clamps, see if this helps. If it does not, I have bigger issues.
Sat in car, the ball-and-chain held the hose, no water. I am perplexed and pissed off at this point. Thinking about pulling the pillars and bypassing the front sunroof drains and tie into the ac line while I am at it. I had used the "long straw" method in the past. I was really just trying to get this car ready to sell. Hence why I have been trying for OEM or OEM "style" repairs and not slapping RTV all over the car.
Thinking about replacing the rubber door seals as well as pulling the interior trim off the front doors to check the condition of the plastic behind it and what-not.
So it appears, not confirmed, that the water leak on the drivers side was leaking at the sunroof drain because of gasket failure even with the "straw" fix. The pics kinda reveal the path of the water with a trail of dirt.
Driver Side Drain, good tug pulled the hose with the drain cap.
DR side drain, dirt shows path of water escaping through side clip, straw could have been longer maybe but foam still failed.
Pass side, good tug pulled hose with drain cap, the zip tie is previous repair
DR side shows dirt path, PS side pretty clean. (zip ties were from hose connection, not used here)
My "hot wheels" track setup to test the drains. Picked up two 1/2" barb to barb and two 1/2" Tees, ran some extra silicone 10mm hose to the AC line. Wanted to test before routing permanently.
All in all, it appears it was the passenger side firewall grommet was leaking, the windshield cowl was leaking into the air intake, and the driver side sunroof drain was leaking post-straw repair either due to shortness of straw and/or gasket failure on the drain. I am likely going to seal the drain caps with RTV and place them back in the pillars. I am hoping my hot wheels tubing track stops the water leak and then it will be routed as to always maintain a downward slope to the AC drain as to minimize holding water in the line as much as possible.
Also wanted to mention that I did have some water in the trunk, this was due to seal failure on the taillights when replacing and I believe some water may have leaked in at the "top" of the trunk near the base of the rear windshield, known area that collects all the crap. Car unfortunately has been sitting for a while. I used just a small bead of I believe RTV or it may have just been marine grease around the rubber seal before installing light. Trying to get this car dried out and cleaned out before we put all the carpet back in and move on to refinishing the sport wheels.
The sun roof drain racetrack appears to be working great. BUT, we found water again in the passenger side. Pictures tell the story, (another?) leak found around the A pillar at the door and fender. Looks like gunk/dirt/pollen/ "froze" the gasket together, and water was leaking in on to the plastic door trim and then dripping down the side onto the floorboard. The water in the carpet clip initially tipped me off.
Pass side floor board, water again. Water in clip. Water drip from door trim to inside car. Tons of crap in weather-strip, car has been parked for a few months.
Same thing happened to me and a few others. You may want to check this post. While there are differences between the Coupe's and sedans, it appears this will be another potential common leak point.
Thank you. If it ain't one thing it's another. I'll read through the thread and decide a course of action from there and post some updates. As of right now the water is staying out, had to super clean the weatherstripping and bring it back to life with some rubber cleaner.
05-08-2023, 12:42 PM
