Car brake failure on sharp incline and back once off incline

Question

I just experienced this. I got a repair done on my handbrake yesterday (it was not holding on sharp inclines before, would slip with clicking sounds). So I wanted to test this and took car on a sharp incline and my engine stalled as I was in high gear. My first action was to apply the pedal brakes. I pressed the pedal and nothing. It felt like car is just rolling freely. I then applied hand brake and that did put some resistance but the car still rolled back.

I managed to get it on a level road and tried the foot brake again and they wouldn't work. I then stopped the engine. After like a minute I turned it back on and I could use the brakes again.

I drove it back home slowly and didn't feel anything odd in the foot brakes. But I am not confident at all in them now.

Can someone please suggest what could have gone wrong that the brakes went off and came back in a minute.

The car is a Fiat Punto evo 2010. It has ABS and I have recently bought it used. I have had some issues with the hand brake on sharp inclines before(with more load in car) but never with the foot brakes before.

Also, no warning or danger lights were illuminated on the dash when this happened.

Update. Probably this is important. The ground was slippery and was covered in small stones (very small gravel like)

Answer 1

Three things:

1. as you were on gravel, was the car really rolling back, or was it sliding back?
2. Since your engine stalled, you won't have ABS or much brake-assist, so your brakes will feel different until the engine turns back on.
3. Since the hand brake seems to have done some braking on the hill, this suggests the pedal brakes didn't get applied. Since they got successfully applied again later, this suggest a temporary malfunction. The best thing I can think of is you are running low on brake fluid and being on an incline shifted the fluid away from the plunger in the master cylinder. Your pedal brake resumed function when the fluid settled itself again.
4. Most cars have a brake proportioning valve that will apply brake pressure at the rear first, once the rears are engaged brake pressure will be applied to the front. If for some reason your rear brakes didn't engage, either because of low fluid (explained in #2) or they couldn't handle the load (the weight shifts to the rear going up an incline), then your front brakes won't engage either.

Look at your brake fluid level, and if your pedal is feeling spongy or softer than it used to, get your braking system bled: you may have introduced air.