Checked the IAT sensor..AOK!

[azcummins]

After wondering why my truck might have large fluc. in MPG (12. 5-15. 5) I decided to yank the IAT sensor and check it. Even after running my K&N for a year now, it is clean. I can easily tell the color of the sensor and the housing.



I guess the bad MPG is due to cold weather (<20 degrees) and winter fuel.

 

[tragicwagon]

az

My truck has a fluc too. When it was new it got 20mpg on the first 3 tanks, then droped to 18mpg. It stayed there for about 8 to 10k miles then droped to 15-16mpg. I took it to the dealer and they couldn't find anything wrong at 22k miles. I also checked the IAT and cleaned it with brake cleaner but it didn't help. But now at 41k miles the last 2 tanks have gotten 19. 5 & 19. 6 mpg. Maybe you'll get lucky and yours will come up too.