2005 chevy colorado
 

Hi there. This is my first time on a forum and I'm here because of some issues that have started troubling me on my truck. It's a 2005 chevy colorado and it's been giving me problems for a while. Quite frequently now when I'm driving on rough roads I'll notice the temp gauge drop then go up again and if it drops too far the rpms will drop briefly. I did change the fuel pump thinking it's related but didnt solve anything. Any body have any idea what could be the problem? Any help appreciated. Thanks