Mine wouldn't work when hooked up, but when i put a drill on it, it did. I gave up and just put it in as it was to fill the dash hole, hooked up. Lo and behold after a short time it worked lol. Still works fine now. I did see the mileage was reading when the needle wasn't as weird as that sounds. I would also say hardened grease, and after a short time of driving, should free it