Starting issue
Thread Starter
6th Gear
Joined: Jun 2019
Posts: 6
Likes: 1
Starting issue
I have a 2014 C7.
if I drive it every few days it starts normally.
if a week or more goes by, when I put my foot on the brake pedal, it does not move at all. When I press the start button, it starts but I’m concerned.
why would the brake pedal be so hard?
as soon as it starts up the brake acts normal with about 1/2 inch of movement.
the car only has 8500 miles.
any thoughts?
if I drive it every few days it starts normally.
if a week or more goes by, when I put my foot on the brake pedal, it does not move at all. When I press the start button, it starts but I’m concerned.
why would the brake pedal be so hard?
as soon as it starts up the brake acts normal with about 1/2 inch of movement.
the car only has 8500 miles.
any thoughts?
Safety Car
Joined: Dec 2012
Posts: 3,812
Likes: 1,839
From: St. Louis Metro East IL
Normal. Power brakes are vacuum assisted. Vacuum bleeds off slowly when the car is not running. After you shut off the car, press the brake pedal several times. You'll notice the brake pedal gets hard after 3 presses or so. Start the car and the intake system pulls vacuum. There is also an auxiliary vacuum pump just ahead of the brake master cylinder.
You should get the car on a slight slope, put it in neutral, and see how much effort it takes to stop the car without power assist. Same with steering effort. You can lift the parking brake switch to stop also.
This is true of any car with power brakes or power steering.
Ron
You should get the car on a slight slope, put it in neutral, and see how much effort it takes to stop the car without power assist. Same with steering effort. You can lift the parking brake switch to stop also.
This is true of any car with power brakes or power steering.
Ron
Last edited by RonC7; Sep 25, 2019 at 01:14 PM. Reason: .
Pro
Joined: Feb 2018
Posts: 685
Likes: 443
From: Texas
I have the same problem as the OP except when my brake pedal goes hard I can not start the engine. Others have said it’s normal behavior but this is the only car I have ever owned that does this. I will look into replacing that check valve as you suggest. Thanks!
Last edited by KCV; Sep 25, 2019 at 03:22 PM.
Racer
Joined: Dec 2018
Posts: 485
Likes: 168
From: Gainesville, Ga.
I have a 2015 Z-51 vert with the A-8....love the car...but have somewhat of a similar inconsistent condition that concerns me...my brake pedal feels just as you describe on occasion...the difference with my issue of concern is that the car wants to "surge forward" after warming it up from the first start of the day only. I have to tap the brake pedal just right and then apply the brake pedal to keep the car from quickly surging forward when first put it in forward gear. I have always let the car idle for a good amount of time to warm it up and reduce rpms before putting it in forward gear(while the brake pedal applied of coarse)...This issue was experienced for several months last year when it was fairly cold out but not cold enough to not drive it with summer only tires...then this spring it went away on its own!...now in the middle of a stretch of 90 degree temps it is back again....grrrrrr...It is not my daily driver, but does get driven frequently on nice days and good weekends.....if this helps...
