Reduced highway mpg in a 1-year-old car. What gives?
June 2, 2014 12:27 PM Subscribe
2013 Subaru Crosstrek XV got 32-33 highway mpg last year. Now it gets 28.
posted by nicodine to Travel & Transportation (20 answers total) 3 users marked this as a favorite
I bought a new 2013 Subaru Crosstrek XV last year, and have put 10,000 miles on it. Last May I took an Iowa-Ohio trip and got 32-33 highway mpg. Just last week doing pretty much the same trip I got 28 mpg. I've measured this both with the onboard computer and just pen-and-pencil figuring.
I first noticed lower mpg (22/28 city/highway) on a trip in November, and was told then by the Subaru dealership that this drop is probably due to a combination of winter gas blend and cold weather. I expected that to change with the non-winter blend gas. Since April or so, my city mpg have gone up to what they were before; highway mpg have not.
The check engine light isn't on, the tires and brake pads haven't been changed, I drive the same way and use the same gas stations, and my tires are full of air. The only things I've done to the car were a camber alignment a few days after I got it, and one oil change in early November.
I did take a high-altitude trip in March. Could something about that trip (the high altitude itself, or maybe revving a little hard trying to climb hills at altitude) have done something to my car?
I called my Subaru dealer and was basically told that in the absence of a check engine light, there's really nothing they can do to investigate or fix anything. This was frustrating and uncomforting.
1. Am I right to be worried, or do new cars normally show this decline in mpg?
2. If the mpg drop is abnormal, what should my next steps be to diagnose or fix the problem?
This car is my baby, I have little mechanical knowledge, and I'm kind of freaking out that I've somehow hurt her or busted the head gasket or something, so any answers would be great. Thanks, MeFi!