# Hard brake, car won't start immediately.



## jyoung61 (Dec 23, 2021)

Hello everyone,

I bought a 2016 Sentra SV in June, pre-owned, and it's been a great car.

On Wednesday morning, first start of the day, I noticed the brake pedal was really hard, as if it had been pumped a number times - which it definitely had not been.
When I pushed the Start button, the dash lights flickered for a fraction of a second, and nothing happened.
I tried again, the brakes were still hard, this time the dash lights lit up and there was a very brief low sound as if the car wanted to try, but it was less than a second. No start.
I waited 20 seconds or so, and on the third try it started right up as if nothing was wrong. I ran a few errands and it was fine for every start.

I have noticed the past few weeks that every now & then the brakes are hard for the first start of the day, but it starts right up. This time was the first time it didn't want to start right away.

Any ideas about what's going on?


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## VStar650CL (Nov 12, 2020)

There's a vacuum check valve on the brake booster that should maintain a tiny bit of vacuum even overnight, and a high-hard pedal usually means it's sticking open and venting the booster to atmosphere. You could also have an issue with the booster itself. Your problem with the startup and flickery lights sounds more like a battery-connection issue.


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## jyoung61 (Dec 23, 2021)

VStar650CL said:


> There's a vacuum check valve on the brake booster that should maintain a tiny bit of vacuum even overnight, and a high-hard pedal usually means it's sticking open and venting the booster to atmosphere. You could also have an issue with the booster itself. Your problem with the startup and flickery lights sounds more like a battery-connection issue.


Thanks. Interesting about the battery connection issue. I replaced the battery in October after finding it dead one morning (it was old, probably the original). It's been fine since then, but perhaps something is causing issues.


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## VStar650CL (Nov 12, 2020)

Since it "woke up" on your third try, it sounds more like a connection issue than the battery itself. One possibility would be the bottom terminal on the ground cable where it attaches to the tranny.


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