Thermostat.

 

Yea it's the thermostat stuck either wide or partially open. You need to meet multiple parameters of the drive cycle before a code will be thrown but eventually it will throw a code for insufficient coolant temp.

Change it out. The cost of a thermostat is most likely less then the added gas from one tank that cold engine is drinking to compensate from not running at operating temp.

Normally the Gage should sit smack dab in the middle and not vary more than an 8th off an inch in either direction regardless of the season.

 

Yes i believe it has real time data, its been a while since i used it last but ill have to take a look this morning to be sure, there are no leaks by the fan clutch and the coolant reservoir is at the correct level and i do believe the cap is functioning priperly also. And yes my gas mileage has nose dived. I know i should be getting better, as it stands right now im sitting with a 1/4 tank left and have only driven about 270 miles if memory serves right.

 

Sounds normal on mine, LOL.

 

I was living in colorado like 3 weeks ago and before i left the temps were in the 60's and i was getting over 300 by the time i hit the 1/4 tank, now im back living in minnesota where it's been in the 30's hehe. I was usually getting around 120 miles out of the first 1/4, granted thats filled all the way up and this last couple fill ups only been getting around 60-70.

 

Mine did the same, before throwing a code....thermostat.

 

You should be running at around 200 degrees. Your fuel economy will suffer if you are running cooler than that. I agree with previous posts that your thermostat may be stuck open or your fan clutch might be frozen and locked. Looked for a fan clutch that does not rotate when the engine is shut off or you see signs of leaking oil at the fan clutch. A new 195 degree thermostat is also easy to change and not expensive.

 

Even if his fan clutch was frozen the temp would stay in the right range. The fan has nothing to do with temp regulation only cooling capacity.

 

I'm going to guess that you've misspoke here.

 

Yeah, the fan makes airflow when there isn't any like at a stoplight. Definitely helps keep the engine cool.