How often do you reset the energy data/MPG? Maybe your most recent trips had a lot more AC usage since it is summer time?

 

I reset every time I fill up with gas or start on a long trip.

 

To to dealer for 5k service, (oil, etc.) now the gauge only shows 30-31 Avg MPG.

There are about six gauges that show MPG. Give us a clue.

 

There is one gauge in the lower middle of the dash cluster that reads "Average MPG"
30.0

etc...

 

Did they use the right kind of synthetic engine oil?
I would check the brake adjustments for excessive drag (including handbrake).
What about tire pressure?
Did you use to have it in ECO mode and not anymore?

Something has definitely changed, you have to figure out what it is.

Good luck,
Daniel

 

Thanks Daniel!! Good stuff to check on...

 

How many miles have you driven since the service?

 

only about 30 miles...I know I should let it settle some and see what happens.

 

They probably reset it. Or had (ICE starter/12v) battery unhooked, which I imagine would do the same thing. If it were a conventional ICE car I'd say they just idled the hell out of it but...yeah. Give it a few hundred miles and see if it doesn't start to climb again, and if so, if it doesn't start to vary much more often and quickly than before. That'll be a big clue that it got reset.

 

Yes, they told me they reset it...
I need to drive awhile and see if it improves before I worry about it again.
It's just that it's new car (for me), getting 40.0+ mpg for 5000 miles whoopee I couldn't be happier!! ...then oil change service and now 30.0 mpg according to the gauge.
Thanks guys for your thoughts...

 

I had the 1 year service done on my car back in May, and my mileage has also been poor the past few months (around 30 mpg). However, looking at my mileage log, the poor mileage started with the tank before I took it in for service.

I blame most my poor mileage on the heat. I usually drive 95% in the city, mostly during rush hour. Out here in Southern California, it's been hotter than normal, so I've been using the air a lot more. Sitting at a long light with the air blasting really drains the battery, causing the engine to run more often.

In the morning, my commute is mostly down hill. If the air is off, I average around 55MPG. If I forget to turn it off (or it's already hot enough to need it on) my mileage drops closer to 40 MPG. On the way home (mostly uphill) I was averaging in the upper 20's during the winter, now it's the lower 20's.

Perhaps your mileage difference is weather related too?

 

A/c is a huge mileage killer! About 10% drain on the highway, closer to 25% in town. Mileage depends on so many different factors, though, it's impossible to say...

A/c is kind of a she. Engines will run more efficiently in hot summer months but for the power drain through a/c.