i drive my 06 ex civic (automatic) 90% highway (60-65 mph on country roads or 70-75 mph on the tollway) and was getting 28-30mpg with gas with ethanol. switched to non ethanol and now get 31.5-32.5mpg. i have 7700 miles on it. after breakin (5000 miles) i switched to mobil one 5-20 weight. been to the dealer twice and they can not find anything wrong. just got back from the dealer who drove it 59 miles and claimed he got 39mpg. on my way home from the dealer i had a 25-30mph tailwind and still got only 32mpg. my son had an 05 civic and got 37-38mpg. he now has a new 07 honda fit and got 35.9 on his first tank. anyone else out there getting poor mileage in there 06 civics. after i left the dealership today i test drove the new 07 toyota camry and may be switching if the mileage doesn't improve in my civic.

 

I am getting similarly poor results, about 26MPG city/hwy mix but the car is new and I am driving it a bit hard and with AC. So, I am going to keep an eye on it.
As for the Camry, you won't do better with that and it's an overstuffed behemoth. We sold a 95 Camry to get the new Civic and didn't want anything larger than our old Camry so the 06 Civic is perfect. Same width, about a foot shorter. The new Camry is huge, I didn't even bother test driving it.

 

Our '06 LX sedan is my wife's daily driver, and she's getting around 35mpg (she drives around 70-75mph). My lead foot only manages about 30mpg (80-95mph)- not bad considering I'm driving it like I stole it. Your lower mpg may be due to hard acceleration or tires underinflated. Your engine may still be a little tight. I'd give it a little time and see if it improves. But the Civic will still get better mileage than a Camry due to lighter weight and smaller engine.

Geno

 

Something is not quite right in your engine unless you drive like your on fire. Hard acceleration kills your gas milage. High speed lowers it also. My 2004 Civic gets 35 mpg with mixed driving (50-60 mph) and lots of stop and goes. My sons tricked out 2001 ex gets 32-34 mpg mixed driving and my daughters 2006 si gets 30-32. You will get the best milage at around 50-60 mph. If you have your mind set on a Toyota, check out the Corolla- its a great car that gets good gas milage and has strong acceleration. In my opinion, its almost as good as a Civic. (but doesn't handle the road quite as well) This is just my opinion and experience. Ken

 

I average 27 mpg in my Si and that's city driving with my foot to the floor most of the time.

 

i average 32-33 thats country/highway in 06 EX