You need to seek a professional. There could be a multitude of problems. You could have a loose part in the engine bay, or you could have an oil problem, or you could have a transmission problem, anything. I would personally say you have sludge in your engine, depends on mileage and how you drive it. Of course I don't own a Focus. Again more reason to seek a professional.
Have vehicle scanned to determine the problem
If you are referring to the Check Engine light it is on because the computer has set a fault code due to a problem with the emissions system.
Have vehicle scanned to determine the problem
Take it to AutoZone, it's free.
The check engine light comes on when the computer has detected a problem with the emissions system. The engine maintenance light comes on when the engine needs some scheduled maintenance such as an oil/filter change.
The check engine light is on because the ECU (computer) has detected a problem with the emissions system. Have the ECU scanned with an OBD2 scanner to retrieve the code that has been set. This code will help you determine what the problem is.
No, but the maintenance required light may very well indicate the oil needs changing. The Check Engine light only comes on when there is a problem with the emissions system.
have vehicle scanned to determine the problem
You have a problem that is effecting the emissions controls. Take it to a qualified technician for repair.
Because you have an engine problem. Take it to AutoZone, or NAPA, and they will check it for free. To reset the computer, disconnect the negative (-) battery terminal and turn the headlight switch on, then back off, and reconnect the battery about 30 minutes later. If there is no problem, the light will stay off. If there IS a problem, it will come back on.
The check engine light on a 2002 Ford Focus can be reset by disconnecting the battery for 1 to 2 minutes. This resets the vehicle's computer and clears the light.
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