[mehoff400]

i changed out my 230 about a year ago for a 250. when doing this ever since then the temp gauge doesn't work correctly. everything i have checked with a temp gun is telling me the engine is running around 180. driving it around it runs normal and i can put my hand on valve cover. yes it is a 12bolt valve cover but its not even a little warm. when warming up the gauge slowly moves up and goes to normal. if i rev the engine it seems like the gauge moves up as i rev the truck up. like the rpms are making the gauge move i know seems weird. i have changed everything from thermostat, temp sensor, and the actual gauge itself with no change.

any suggestions?