Q: Brakes don’t work when it’s cold

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My car is a 2012 Ford F-150 XLT 3.5L V6 Ecoboost, automatic transmission, with 55,000 miles. I had a brake vacuum booster replaced at 30,000 mile due to excessive noise by my local shop. Then at 55,000 miles, the brakes seemed to freeze up when going down the road in cold weather. The problem was so severe, I couldn't apply the brakes and nearly hit the vehicle in front of me. I had the pump replaced again and the issue seemed to be resolved for a few days and then came back. The problem has gotten worse. Now, when you first start the truck, you have to wait for the pump to build up vacuum or you can't push the brake pedal. Help, please.

This issue of brake vacuum pump failure is a dangerous issue and if it fails while driving you may not be able to stop as quick as when the brakes worked normally. The brake boost pump is designed to assist the 3.5L V6 Ecoboost engine. The 3.5L V6 Ecoboost engine does not have enough vacuum to supply the vacuum brake booster by itself without help from the vacuum pump in question. Without this additional pump, the brakes do not get enough vacuum to the vacuum booster to assist stopping the vehicle. This results in a hard brake pedal. The brake vacuum pump has a high failure rate, due to internal corrosion causing pump failure. The only known fix today, even though it may only be short lived, is to replace the vacuum pump. Until there is a recall, a Technical Service Bulletin (TSB), or some sort of fix, all that can be done when it fails is to replace it or park the vehicle not drive it. There is also a national shortage of the pumps due to the high failure rate. The NHTSA has received enough complaints that they opened up an investigation. The investigation opened on June 22, 2015 for Brake Vacuum Pump Failure and had preliminary evaluation #PE15026 assigned. You may file your own complaint by calling the NHTSA Monday-Friday 8am to 8pm at (888) 327-4236, TTY: (800) 424-9153. NHTSA: For detailed information & supporting documents, see the official NHTSA page concerning investigation #PE15026

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