NHTSA Complaint #11672907 — 2022 NISSAN SENTRA

I experienced a second brake booster failure within 1300 miles of the replacement. The booster should be available for inspection, but I do not have it. The dealership has it. On May 9, 2025, at 38,349 miles, my booster failed, experiencing a very loud audible boom and insulation hanging under my car. It was taken to a Nissan dealership and they verified it was something they’d never seen before. It was replaced, then on June 23, at 39,630 miles, it failed again. I had my 4 year old daughter in the car the second time and thankfully was able to stop, but it could have been catastrophic in heavier traffic or at higher speeds. It was inspected by a second Nissan dealership. They advised there was oil in my brake fluid, but did not advise how it could have happened. They also said they aren’t sure what caused it and they’ve also never seen this before. One failure is rare, a second within 1300 miles is extremely rare. The symptoms, I feel, began in January. During a warranty strut replacement, I advised that my brakes were doing something strange and I wasn’t sure if it was the brakes or transmission. I was recommended to have a cvt flush and brake fluid change. I feel this was the booster, but the dealership said there are no symptoms of a failing booster. If those were not symptoms of the booster, then the first symptom began around May 5. When I would start my car, I noticed the brake pedal was stiff until I started it. It drove normal until I pressed the brake while idling in my driveway preparing to leave and heard a loud boom, followed by a hissing sound coming from my brake and a very stiff pedal. My brake is still very stiff when I go to start my car (as if I’ve pressed the brake multiple times, but I am pressing it for the first time). This is potentially the first symptom I experienced before the first failure, it’s a symptom that has not gone away since the first failure. The first failure was also reported and the complaint number is: 11663673