my engine temp gauge doesnt seem to work anymore... if i drive my rex long enough, it will sorta almost go to the first line but then it drops back down. So my question is, is there an aftermarket engine temp gauge i can buy? and where can i get it? Thanks

 

You could get an Autometer water temp gauge. Or any other brand for that matter.
It will probably give you a more accurate accessment of your engines temp.