I Just got some flowmaster 40 series installed on my 1999 Dakota 5.2 . Once in awhile the check guages light will come on and the temp guage will read all the way to the hot side. AFter about 30 seconds it will go back to normal and do it again out of the blue some time down the road. I know its because of the new exhaust because it never happened before. Anyone have this problem? Anyone know what it is?

 

Was it welded on? Did they disconnect the battery before welding?

Sounds like either a sensor problem, a wire problem, or an ECU problem.