I have a 2004 Pontiac Sunfire, and this morning the speedometer stopped working properly. When I am completely stopped it now reads 25mph. All other gauges work fine. For the past 2 weeks the needle on the speedometer has been sticking. For example if I was going 60 and accelerated to 70 instead of the needle accelerating with me it would jump from 60 to 70. Do I need to replace the instrument cluster or could this be a problem with the speed sensor? If I have to replce the cluster looks like that the entire dash needs to be removed to get to the cluster. (I only took a quick glance.) Is this correct, or are there screws that I am missing to where the driver's side can be removed for easy access?