Hey everyone. I was hoping somebody could help me here. I have a 2006 F-150 Lariat Crew Cab, and a few months ago my engine light was on, but it was running fine so I ignored it and a couple weeks later it just shut off and hasn't been on since. Now it's winter here (I'm in Winnipeg Manitoba), and temperatures have reached about -40 Celcius, and now I've gone from getting about 560 KMS per tank to about 460. At least it says 460, although today I filled it up, it said I had 460 KMS before empty, I drove about 30-40 kms, and now it says I have 368 left to empty. Has anyone had anything like this happen? Also, after the truck fully warms up, I start hearing a light thumping noise in the front end when my heater is on. Any help would be appreciated. Thanks

 

When your check engine light comes on it is there for a reason. You should've at least taken and had the codes pulled to see what was causing it.

Also, welcome to the site.

 

I was too busy working to bring it in and it turned off before I had a chance. I'm well aware that it comes on for a reason. I was trying to see if anyone had any advice besides just bringing it in. Thanks anyways.

 

I would expect a bit of a decrease in fuel economy for such "extreme" cold weather (texas boy here), however a 100km (60 mile) difference is kinda weird. I don't know how long you idle the vehicle for. I believe for every hour of idle time on that motor you use about a gallon of gas. Colder weather typically calls for more fuel in the mix to keep you from running lean. This is due to the increase in oxygen from the colder, denser air. What size tank do you have?

 

It's a 100 liter tank I believe. Yeah I mean there's a few things that contribute to it I'm sure. The richer fuel mixture that the engine uses in the cold, the fact that I have to let the truck warm up for a good 5 - 10 minutes before I start driving, plus I have my heater blasting the whole time. But as you said, a 100 KM per tank difference is pretty extreme.

 

Be aware that there are hundreds of issues that will post the "Check Engine" light. Some as simple as a loose or bad gas cap. Pull the code..... I believe an AutoZone store will pull it for free.................