Two problems related to brake master cylinder have been reported for the 2011 Buick Regal. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2011 Buick Regal based on all problems reported for the 2011 Regal.
During periods of high heat (and only high heat) after being parked in the sun, when the vehicle is being driven at highway speeds, the brake pedal will stiffen and slow the car down. The steering wheel column will violently shake, as if the calipers are stuck. Once parked, all four wheels are hot and omits a burning smell. I have replaced two tires, 2 front calipers, front brake pads, all hoses and front rotors to no avail. Brake booster and master cylinder have been checked and are not the issue. All possible issues have been addressed within the last 8 weeks. Friday (05/14/21) the same issue happened again. I am at my wits end trying to resolve this issue.
Six months after purchasing this used vehicle (with 29,000 miles on it) it completely stalled on the interstate while driving about 65 mph. It started braking by itself making it difficult to get to an emergency pull off area. This could have caused a serious accident considering it was rush hour. I took it to the dealership where they told me that the "throttle body" needed to be replaced. After getting it repaired the car drove fine until this year. At about 55,000 miles my car would start shaking very hard, brake pedal was almost to the floor, and it was almost impossible accelerate. I had to pull over and restart the car. This happened atleast 4 times. Eventually my car stalled out on me again while driving on the interstate. Once again this February the dealership blamed it on the "throttle body" and a powerline that was "completely corroded". After having them replaced, it drove ok for only a couple of months. Then all of a sudden in June my car started shaking very badly while driving on the interstate and I noticed that my brake was stuck I put my foot under the brake pedal to pop it out and the car then drove ok. I took it to the dealership and go figure the "throttle body" needed to be replaced, brake master cylinder had to be replaced, brake vacuum booster needed service, brake fluid system had to be flushed, and the engine air filter needed to be replaced. I walked away with a $300 bill because the warranty only covered some of the problems. One week later while it was pouring rain I was driving on the interstate and my car completely stalled for the 3rd time. A tractor trailor almost lost control trying to prevent hitting me as I slid off the interstate. Once I was safe I tried to restart it and the key broke off in the ignition. Now the immobilizer module has to be replaced. Please note that I keep the maintenance up on this vehicle.