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Q: Brakes don't work very well when it's cold

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Whenever it is cold outside, I go to start the car and it's a bit slow to turn over. The engine revs high, too. My problem is that I'll pull out of the driveway, to the end of my street, and then I'll have very little braking power available. After coming to a an extremely slow stop, the brakes start to work. This only happens in the morning. What could this be?

You have two different issues here. The slow crank may be that the battery is getting weak. It may need to be replaced or the terminals cleaned. The other issue of the high idle and braking issue is probably due to a failing brake booster. You either have a vacuum leak in the brake booster or engine, or a bad brake booster check valve that leaks and will not hold vacuum. Have the battery tested and replaced, the brake booster check valve inspected, and engine or booster checked for a vacuum leak. A certified mechanic from YourMechanic can provide this inspection at your home or office.

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