I seem to be having a hard brake pedal when I depress it prior to turning the car on. Sometimes I have to press the brake pedal and start button more than once to get the car started. Is it possible that the master cylinder needs to be replaced?

 

That's normal, especially on a new brake switch. press harder lol.

 

Had this issue before. Replaced the vacuum check valve and rubber grommet and was fixed. I think parts were under $40 total.

 

Try replacing the check valve on the booster along with the grommet. It helped my pedal. Cheap fix.

 

https://www.clublexus.com/forums/is-...overnight.html

Lou

 

Had the same issue. I replaced the check valve and grommet 1st but it didn't fix it. Ended up being a leak in the brake booster. Had it replaced under warranty.