As the title says, I'm experiencing bad gas mileage in the cold weather. I know most vehicles get worse mileage in the winter months, but I went from around 15-16 in the warmer months, down to about 10! Is that normal, or should I be looking at something else? I appreciate any responses.

 

Sounds too much. I changed tires to winter tires and with winter gas went down from 16 mpg to 13 mpg.

 

Are you using the OHD to calculate or using your mileage and gallons used on paper and dividing?

 

Yeah, 5 to 6 is a little much, but not out of the realm of possibility. Winter blend gas hurts as does the cold weather which has the PCM richening the mixture. Add a CAI to the mix and it will hurt a smidge as well. Hot air into the throttle body yields less power but better fuel economy and cold air does the opposite.
Three to four is the norm, so you ain't drastically off.


I just saw you have a power wire also. That's probably where your difference is coming from. It fools the PCM into thinking it's colder than it really is...

 

I'm just using the OHC, which probably isn't too accurate. I didn't really think of the CAI or Power Wire...makes sense. So I'm probably within the norm. Thanks guys! Maybe I'll disconnect the power wire and see if my MPG improves.