This is my first time on this website so I do not know if I am doing this right. It is going to be a very long topic but PLEASE take your time to read it and give me some advice on what to do.
I got subwoofers yesterday and I went to my friend for help. So of course we needed to get the hotwire from my amp to my battery. So we tried looking for a boot, but we could not find any. He had an idea to drill through my firewall. While he did that I went and popped my hood. We had a light shining from where he was drilling so I could see if there was any holes being made from under my hood. He drilled and he drilled but I could not see any light. We failed getting the hotwire to my battery. blah blah blah [fastfoward] > I started my car and then I started hearing a hissing noise in the cabin. The noise was directly in front of me down by my foot area, it was behind the brakes. I got completely scared. Then the “check brakes” came on… blah blah blah [fastfoward] > His dad came home (keep in mind that his dad is an actual mechanic and he has ALOT of knowledge about cars. He does not work at a mechanic shop, he just volunteers to help at an autoshop for college, he built an engine at 9 years old with HIS dad. So lets just say he is way above average in car knowlege). I told his dad everything that happened and His face was priceless. He popped the hood and He knew exactly what happened. He said that my friend drilled through the brake booster, and thats why the hissing noise was present. The hissing noise would stop when I applied the brakes “kinda” harder. Then when I depressed it the hissing noise came. His dad got silicone adhesive and tried squirting as much adhesive he could through the tiny hole in the firewall so it could reach the brake booster. We both knew it was DOUBTFUL that it would stop the hissing. We took it for a test drive to see if the brakes would still work. The drive was actually good, the brakes were normal. Everytime the car accelerates the hissing would stop and AGAIN everytime the car would brake, the hissing would stop. That night the check brakes system light was on. The next day the check engine light came on, so I called him and he said that it would come on because of the air/vacuum leak.
Since it was his sons fault. (it was an accident, crap happens) His dad said for me to not worry about it and that he would fix it. (that would be in a week or two because he has a project he is currently working on). I am currently still driving it. Breaks are normal. Just the hissing noise is present and the check engine light and check brakes system is on. I even went on the highway and went 60-65 and did a hard stop. I know that might sound stupid but the brakes were still normal. Now the size of this hole that my friend drilled through is probably the width of a toothpick, or maybe even a toothpick and a half. So that hole is really small. maybe that is why I am not losing alot of break power. With the given information of the size of the hole, would it be POSSIBLE for my friends dad to just take the brake booster out and just PATCH the hole? I mean it IS a very small hole. I am just glad that my friends dad is able to do all this labor for free, even if I have to go to the junkyard or online to get me a new brake booster, but i really do not want to spend all that money on a new brake booster.