2010 C30 2.5, 80K km.

Three times in the past couple of weeks after sitting cold for an hour or so when I start up and am coming out of a parking lot and then have to stop before entering the roadway my brakes don't respond immediately. I'm never going more than 30 kph, and they do eventually kick in but not before I wonder if I am going to be in a collision. I had them inspected last week and had the lines flushed and fluid replaced. It happened again. I couldn't find a technical service bulletin relating to this and my mechanic has no explanation. Anyone have any insights?

Thanks in advance

 

what do u mean by not respond immediately?? brake pedal harder then usual?? not respond @ all?? what's your engine rpm during braking??

 

Thanks. I push on the brakes and initially it slows but then get no progressive braking -- not mushy, I just have to put my foot down harder than usual and eventually (like a second or two delay) it stops. RPM = 1500-2000, in first gear. Most of the time it is normal, firm pressure on the brakes, car stops as expected. It's happened once more since the original post.

 

seems like your brake vacuum pump is acting up. during the couse of time your brake vacuum pump is loosing vacuum to engage the brakes properly. does it happen afyer the car warms up?

 

it sound like the brake vacuum problem to me. in order for a braking works u need to use vacuum too. on the inital starting of the vehicle, since the car sat over a long period of time some of the vacuum will disapear. and thats when the brake booster & vacuum pump comes in. since your problem never happen during normal driving so i would focus more on the vacuum pump, althrough the booster could cause that too. here how to test them, with car running on idle, slowly press the brake a few time then hold the brakes see if u could hear hissing or air leaking noise, if u do then there is a leak on your brake booster. with the vacuum pump test, with the engine off, key in second position, hood open, with parking brake on, press the brake pedal a few times, u should hear a motor sound running everytime u press it. if not then ur vaccum pump is not working. if everything is working normal, then u may have a intermittent faults on the vacuum pump or vacuum 1 way valve.