VW Jetta TDI Performance & Economy Upgrades - Part IV

Now that we have an AFE Stage 2 Si Cold Air Intake installed in our 2012 VW Jetta TDI Sedan, it's time to see what kind of fuel economy gains we'll get from the intake.  We originally took a trip from St. George Utah to Ely Nevada with a stock car to get a fuel mileage reading.  As mentioned in Part 1, this trip involves a decent amount of uphill driving, and our fuel mileage was 36.03 MPG on the first run.

It was about 100 degrees Fahrenheit in St. George the day we left on our first trip in August.  This trip was in early October, but it was still pretty warm, about 90 degrees.  Temperatures were cooler on the trip, especially as elevation increased.  After filling up the tank, we took a picture of the odometer.  924 miles on the car.

Just like our original trip in August, there was about 800 pounds between people and luggage in the Jetta.   Just like the first trip, we didn't stop much, averaged about 70-75 mph, and just drove "normally."  When we got to Ely we were very interested to see what results, if any, would come from having installed the TDI cold air intake from AFE.  After filling the tank in Ely, we took another picture of the digital readout.

The odometer now read 1,141 miles.  The receipt from our fill up in Ely showed that we had used 5.634 gallons of diesel fuel.

Doing the math, we take 1141 miles minus our starting miles of 924, for a total of 217 miles traveled, exactly the same distance as our original baseline trip.  Dividing 217 miles traveled by 5.634 gallons of diesel fuel, the mileage on our trip with the AFE cold air intake installed was 38.51 miles per gallon.  That's an increase of 2.48 miles per gallon - not too shabby.   Not scientific, either, but our best guess is that the AFE intake gave us a boost in fuel economy as advertised.

In the next part of this blog post thread, we'll see what fuel economy we get on the "downhill" return trip to St. George, and if this almost 2 and a half MPG increase was a fluke, or something we can expect to continue to get.  Thank you for reading, and remember we have a huge selection of performance diesel parts for VW TDI's, Ford, Dodge and GM diesel trucks.