I got a 07 2.3 manual ranger and when it sits, no driving, the temp sits at about 170(checked with a OBD2 scanner). Is this too low? What does y’all’s run at? Also, would this cause any drop in fuel economy?

 

2001-2011 2.3l Rangers used a CHT(Cylinder head temp) sensor located between spark plugs 2 and 3 in the valve cover
So doesn't read coolant temp, reads head metal temp, just FYI

But it does read high, coolant is about 15-20deg cooler than the head metal

Normal coolant temp after full warm up is about 190degF, so CHT might be 210degF
Ford dash temp gauge is 200degF at 1/2 way

So CHT at 170degF does seem too cool after full warm up, yes, lower MPG, not a lot but................
And dash temp gauge should also show lower, 1/3 maybe
Might be stuck open thermostat