So here are the symptoms: Car temp displayed on cluster usually sits at the 1/4 line and fluctuates minimally (maybe halfway to the halfway point). Last week or so it has been sky rocketing when in traffic, almost hitting the red portion at hot. Thermo fans come on full blast to cool it but doesn't seem to have much effect till driving. I have installed an aftermarket water temp gauge located in the centre of the top radiator hose. This temp doesn't seem to move and is relatively cold (80-95 degrees). Am I on the right path thinking it's the water pump considering I'm getting 2 completely different readings from 1 sensor in the block and 1 in the radiator hose? Also to consider when I pulled in at home tonight the radiator cap was not hot but when opened coolant was bubbly. Is going into the mechanics tomorrow just wanting some more knowledge on the situation.