Reduced mileage on hybrid after service

Dear car experts -

I took my 2003 Civic hybrid to the Honda dealer for a 50,000 mile service, and since then (last month) my mileage has declined by about 5-6 mpg. Does anyone have an explanation for this? I got new tires, but there was nothing else done that was outside the normal service. I want my mileage back!

Thanks much for any help -


Were the tires the same size??? If they were a little wider it could cause higher rolling resistence…thus lower gas mileage.

Winter weather always increases fuel consumption. How does this situation compare to past winters? Also, I hope you are measuring mpg properly (actual miles, actual gallons, do the math) and not just believing a mpg gauge or a computer.

Thanks -

I’m just comparing the odometer guage in the car to what it was reading previously. So whatever the true mileage this is a strong relative decrease. Also, we don’t have too much winter here in Southern California, but thanks for the suggestions!

Thanks much, I thought about that. Could it really make that much difference?

Even if they are not wider, some brands of tires have a higher rolling resistance than others. I suspect that the new tires are not the same brand/model as the old ones.

Has there been any engine performance issues other than the noticed lack of mileage per gallon?

Perhaps a brake isn’t fully releasing causing a drag.

Check for anything that may be loose or disconnected.

Is the transmission shifting properly? (IF automatic, perhaps hanging up in a gear before shifting?)

Hybrids are getting somewhat complex to say the least.

Any changes in driving habits, extra weight in vehicle, change in normal routes (more stop and go?), traffic volume? All contribute to a decline in fuel mileage.

Thanks for all the suggestions. My car (standard trans.) and I aren’t too exciting; we haven’t changed our habits much in the last month and she runs as well as she ever did (which is to say very well). I guess I have to go with the tires as the cause, and just accept my loss! Thanks again-

They could also be slightly larger in diameter which will make your odometer read lower giving you lower apparent gas mileage.

If you got a front end alignment, things can change even if the alignment was done right. Especially if it was done wrong. Maybe the engine control computer was reset and it has to relearn how you drive.

Check your tirite pressure. Just because they were installed does not mean they used the proper pressure level. This would not yield 5-6 MPG but maybe 50% of it due to higher resistance tires and possibly low inflation.