Ok I can't figure out why my temp gauge wont work... I put a new sending unit on the truck but it still does the same thing. It's not that it don't work at all it just doesn't come up past the C. After the truck has been running for a while the gauge will move up slowly, almost cutting the C in half on the gauge, but will never reach the normal mark. (It worked one day with the old sending unit about a week ago) I can't figure this thing out...help please...
I just got the truck about a month ago and it had been sitting for a while. It is a 89 2wd 300 straight 6. It only has 74000 original miles. 3000 put on it since 2005, and I put 1000 of those on it. Its a great truck. Had a fuel problem when I got it and I changed the regulator, fuel filter, plugs and wires, air filter(all the basic stuff) and problem fixed.

 

what temp thermostat does it have and what is the water temp in the rad while hot?

a 160 degree tstat will run right on the edge of the bracket...and actually a 160 tstat is much better for the 300-6 anyways...it allows you to do the 16deg timing bump and get almost a full 24mpg....

 

A lot of people say that's where their gauge reads. That's where mine reads too, now that I have a decent engine in there.

 

If you do Error code scans at warm idle & you don't get an ECT senor error, your fine.