Unexpected bump in mileage?

Wankel7

Veteran Member
Joined
Dec 25, 2012
Location
Indiana
TDI
2003 Jetta Wagon
I haven't changed my driving style or anything on the car... just fuel.

I filled up with some premium diesel....they claim 50 cetane when I called them. I took a 275 mile trip and observed normal mileage. Mainly 60 to 70mph with two people using the AC. I hand calculated 47.5mpg.

I topped it off again and just put on over 650 miles. I haven't filled up yet but SG says I am averaging 57.5. I thought it might be SG having issues but I have never gotten more than 500 miles as the needle hit 1/2 tank. This time it was 570 miles.

Could a higher cetane cause this big of a bump?
 
Last edited:
Top