I was wanting to get some opinions on this. When sitting at an idle the fan will not cool down the engine temp. It actually starts to raise when the fan comes on, as soon as I give it a little throttle the temp will start to drop. When riding around it will act normal. The fan will cut on at 204 and start cooling it down. I am thinking maybe water pump impeller? I have been experiencing some vapor locking as well so im sure a new fuel pump is in order but im not sure if that could the source of the problem. What does PRC say?