Brake Problems On Cold Days?

Question

I am having very unusual brake problems on my 2002 Nissan Altima with 94k miles. Recently the weather has turned extremely cold and on 3 separate cold days, my brake padel did not press down after driving about 1/4 mile.

When I start the car and put the car in reverse, the brake padel worked fine, but after I drove off and came to the first traffic light I was not able to stop because the bake padel would not go down. This happened on 2 different occasions. After 10-15 seconds of tapping onto brake padel caused it to work properly for the rest of the day.

I took the car to the dealership for inspection and mechanic said that he does not see anything wrong with my bakes. I did tell him that this happens only on the extremely cold (temperature below 20 degree F) days. This is turning into a huge problem for me. I was not able to stop at the red light. Luckily, no one was coming from the other side.

Does anyone have any idea why this could be happening? Any help will be appreciated.

FYI - I had brake fluid flush job done when the car had about 73k miles on it, which was about 9-10 months ago.

Answer 1

I agree that the brake fluid probably needs to be changed, however it would be due to the moisture in it.
The chemical composition if brake fluid is Glycol based, which is a hygroscopic element (moisture absorbing).
If the fluid has a large amount of moisture in it, it would be possible that the fluid is freezing on extremely cold days.

This is the only scenereo that I can think of that would be related to cold weather operation, otherwise there is a mechanical failure at the brake pedal that is keeping it from working properly.

Answer 2

I see that you already had the fluid flushed. Try removing the cover to the master cylinder where you add the brake fluid. Check for any discolorization. If it is not clear, but muddy or murky looking, then i would go back to the repair shop who serviced the brake fluid. The system may be contaminated and the moisture will freeze up the brakes. Your booster runs off vacuum which your engine produces and this can also give off moisture which will "freeze" the brake pedal. But in any case, have everything thorughly rechecked. If the dealer didnt see anything conclusive as far as the peration of the brakes, then i would have to assume the brakes are fine. Your car uses DOT 3 brake fluid, and DOT 5 is a silicone fluid. You may want to consider another brake fluid flush and convert to DOT 5 fluid. DOT 5 does not absorb moisture and is much more expensive due to the low boiling point.
good luck....

Answer 3

IIs it a real hard pedel when you try to stop?? like pushing down on a brick??? Im sure you have one it very well could be the brake booster. That is on the firewall of your engine or on the wall seperating you from the engine compartment. Right in front of yu on the other side of the wall is the brake master cylinder and i would belive that you car has one the brake booster that is. the master cylinder is bolted to it, usually a black dounut looking unit. If not a brake booster you Have you had your brakes done recently??? If things were not tightened down right like a caliper then you would experence problems and it even throws your anti lock brakes off also. If you have done some hard driving riding your brakes coming down long streaches and hard stops i mean really heating up the fluid then you may have boiled your fluid but i really doubt it. you have a mechanical problem Your acuater may be jammed also that is the valve that distributes fluid to front and rear brakes. Good luck

Answer 4

It sounds to me like the braking system needs to be bled out. Is the brake fluid original? Shops offer "brake system flushes", as brake fluid, like any other automotive fluid wears over time. Also, when its cold the brake fluid is "thicker", so any air in the system would cause more back up in the system, thus having no pedal.