Q: ford focus mk2 2.0 car idle rough and have no power.change.put feet on brake padel-car goes limp mode. 2005 Ford Focus

Hello - check first for problem codes, whether the Check Engine light is illuminated or not. The change in rough running behavior when you press the brake pedal may indicate a failed brake booster. A ruptured diaphragm in the booster would make the engine idle rough, and possibly cause other "drive-ability" issues like poor power. I would recommend a rough running inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.