My car ran fine and had no problems. One foggy morning however, I was driving and stopped at a stop light. While pressing the brake, the engine suddenly revved up. The car lurched me toward the stop light. I took it to the dealer, but he didn't find any problem. This happened again one rainy day. The engine started revving. The car lurched me toward while I pressed the brake. What could be causing this? I appreciate your help.
It is possible that your brake master cylinder is leaking brake fluid into your power brake booster. Your power brake booster is connected to engine vacuum so if a flammable liquid such as brake fluid were to enter the power brake booster, the engine would be able to inhale that fluid.
When the excess ’fuel’ is added to the engine, the powertrain control module (PCM) will increase the idle speed to compensate for this extra ’fuel’. I would recommend having this high idle speed issue diagnosed by a certified mechanic for best results.