I have a similar problem.. My needle only goes up to 3 notches above C. doesn't EVER get past that. When my CT26's coolant hose blew i lost more than a gallon of coolant & thats when its started rising & it rose to half. Ive changed the sensor, even the gauge from the cluster itself... Same story. Im running radiator with A/T lines which i don't use because i have a R154, 10 blade fan, Tundra fan clutch. Every time my old man rebuilds an engine the son o bitch takes a long time to heat up. Same story with his Dodge, takes a long time to reach the middle of the gauge but at least IT GETS there. I have to let my car idle 15 minutes to watch the needle go 2-3 notches above C....
well what can i say? get a new sensor & if its the gauge i have an extra! :evildeal: