Honda Civic Hybrid battery update brings fuel-economy complaints

Honda has issued an update for 2006-2008 Honda Civic Hybrids to address premature failures of the expensive hybrid battery system in its cars. Owners are being notified to return their vehicles to the dealer for updated software that applies the battery-management logic of the later model 2009 and 2010 Civic Hybrids.

A common complaint in user forums, however, is that some drivers have seen worse fuel economy since the update; some say up to 10 less mpg.

Honda says that the cars’ EPA ratings of 40/45 mpg (city/highway) do not change, and that fuel-economy-conscious Civic Hybrid drivers have probably learned to maximize mileage and may now need to learn new driving strategies to maximize mileage under the new system. The software change did not require the company to recertify the cars to record new mileage ratings.

In our testing, the Civic Hybrid got an excellent 37 mpg overall. Dropping to 27 mpg represents an additional 10 gallons a month for the average driver, or an annual cost of $336 (at $2.80 per gallon).

Our reliability data shows Civic Hybrids and other hybrids to be very reliable overall.

Our reliability data on first-generation Honda Insights, shows a higher than average number of electrical problems, some of which are related to the battery.