OK so my temp gauge when the vehicle is off is all the way to the right or "H". When I start the vehicle after its been sitting for a few days, the needle only advances to the "normal operation range" ie in-between the two hashes. As soon as its warm, its reading hot.... thermo scanned engine, thermometer in rad etc, vehicle is not over heating. Changed temp sensor at block, same results. do these needles get "off" the mark? can they be adjusted? can the gauge be serviced? or do I need to just replace....if I can find one.