2 weeks ago i took my first long trip with the civic hybrid (automatic transmission). i was driving from san jose,ca to los angeles the first day, and then on to san diego the second. LA is around 400 miles or so from san jose. i only got my car in march and with each tank of gas my mpg has increased steadily from around 42 to about 48 currently. i had just filled the tank the nite before i set off on my trip and cleared the trip odometer. when i started driving for about the first 1 1/2 hours or so i was pegged at 48.1 mpg. i was crusing about 70 miles per hour the whole time. then, my mpg slowly started to drop a little about every 5 minutes or so until i was at 45.7 mpg. Hwy 101 is fairly flat where i was at the time, which was south of salinas. i pulled over at a gas station thinking maybe i had a flat tire. but all was well. my "hot" tire pressure was in the high 30s. the rest of the trip progressed with the mpg staying at 45.7 and occasionaly hitting 46.1. the entire time i was in LA and san diego doing a "normal" type commute to a class i never went above 46.1 and ocassionally went down to 45.7. granted, 46 mpg is still good but i figured once i finished the long trip and wound up at my destination and got back to regular driving my mpg would go back up to where i thought it would be, around 48 or so. the next time i go to get gas i will reset my trip odometer which is what i normally do when i get gas. i didn't reset it the whole 1 week i was in southern cal since out of curiosity i wanted to see how many total miles i drove on the trip.
on my drive back up from LA to san jose i got 45.7 almost the entire way, going about 70mph.
does any of this seem strange? thanks for any information!