Hello and Welcome! I'm Billy and i will assist you with your inquiry. Feel free to ask if any further info is needed.
Please confirm the year of your focus, as you say it is a 1996 (focus started in 98)
do you have any other symptoms or warning lights getting on...etc...?
needle goes up and down, meaning it fluctuates?
and do you have any warning lights on, or flashing?
Are you still there?
There are two very common issues, causing this problem. So common that Ford issued a bulletin. The engine wires and ground points in engine bay need cleaning and tightening. I will include the bulletins so you check the details and proceed accordingly to get your fix:
click here1 and here2 for details
Thank you for your trust! Get back to me if you need more info..if not, Thank you in advance for the positive rating...http://www.justanswer.com/car/expert-billy/And do not forget to check out the other categories (health, law, taxes, vet, etc...)