To troubleshoot a Ford Focus, identify the specific problem and the symptoms associated with it. Common problems with a Ford Focus include the ignition key failing to turn, engine issues and starting delays. Other problems include loss of power and vibration when starting.
Lack of lubrication in the ignition system can cause the key not to turn in the ignition. To fix this, lubricate the ignition system regularly. A worn out battery or misfiring spark plugs may cause failure of the engine to start. To rectify this, replace the battery, adjust the battery terminal connections and replace the spark plugs with clean ones.
A dirty fuel injector or a faulty mass air flow sensor can result in engine hesitation when accelerating. Cleaning the injector and replacing the mass air flow sensor can fix this problem. A defective front axle or failure to apply parking brakes when parking a Ford Focus can lead to loss of engine power when going uphill. Replacing the front axle and ensuring that the parking brake is applied when parking the car can eliminate this problem.
A worn out brake rotor or a stuck brake caliper can cause the Ford Focus to vibrate when starting. Replacing the brake rotor and including brake caliper service when the brakes are due for maintenance can help to resolve this.