Have you manually calculated the mileage?
I wouldn't rely on the onboard computers.
Only refill when the tank is nearly empty.
Slight variations and errors get magnified when you refill a half full tank.

 

I manually calculate every tank. I generally refill when the tank is half empty. From the purchase of the Camry Hybrid the middle of March 2009 to the middle of August 2009 I had no problem and was averaging over 36 MPG refilling the tank when it was half empty.

 

Can you post a clarification?

Did your mileage change only AFTER you moved?

If it is after, there could be a few things that could affect mileage...
- different type of commute, some are better suited to Hybrids then others,
- different types of roads. Some seem to have more rolling resistance than others, and your difference is similar to what I have observed just driving on different highways around here.
- try going back to Tier 1 gas stations for 2 - 3 tanks and see if your mileage returns.
- If your wife drives the hybrid like mine, it could be worth 3 - 5 MPG right there!

An interesting puzzle...

 

About 30 days after I moved from Ledbetter Kentucky to Opelika Alabama. I tend to think that a different driver plus differing gas stations when I came down here. It seems to drop down and then go back up for several tanks of gas and then take a drastic drop again. I'm going to stay with Shell for several tanks and see what happens.

 

We had a change in FE after my wife retired (she is the primary driver). She retired from teaching in June and the car was driven mostly in town instead of her old mix of 20 miles city and 20 miles freeway each workday. The FE dropped from between 33 and 34 down to real close to 30. At first I tended to blame her driving habits, summer gasoline, etc, but after a while I noticed that the best we got was the 30 mpg unless we went on the freeways - then it jumped back up to 34 to 35.

We live in a town that is all hills - on the foothills of the San Bernardino mountains. All primary shopping is at leas 1K feet below us, so wherever we go we are going either uphill or downhill, which distroys the fuel economy. I still love the fact that we get the 30 mpg but would really love to get to the rated 34 but don't think it will happen in Yucaipa!

 

When you are driving, are you noticing the engine turning off?
I'm not sure why, but there are times when it doesn't act properly.
Today I drove 25 minutes on the highway and then I sat at a security booth for about a minute (the heater was off) and the engine was running. I put the car in park and it still ran. It doesn't usually do that, but it did that today.

 

I lived in Loma Linda / Mentone California for a while so I know what it is like going up and down the hills in California. We have basically a low lying plain here in southern Alabama but the lack of the 35 miles one way to work each day could have an effect on the driving of the Camry. I do not have the engine turning off or on on a random basis. Just when I'm driving in start & stop driving does it go into electric mode.

 

I have seen that happen to me occasionally. I just let off the brake, let the car move forward a foot or two, and then in about 7-10 seconds the engine turns off.

 

Since you fill up at a half tank, I'd recommend sticking with one brand for 5-10 fills. My reasoning is that you will only be diluting whatever gas you have in the tank unless you are willing to run the tank down to 0 miles remaining for 2 tanks. Also, do you fill your own tank? If not, the person filling it may not be filling it to the same (approx.) level and that could also cause mileage to go up (short fills) and then one time they fill it right up and your mileage drops.

One more thought, does the car's tank MPG follow your hand calculated MPG? ie. a constant discrepancy. While the computer may be optamistic, it should be consistent and it basis its numbers on fuel burned over miles traveled. If it is a inconsistent fill issue then your calculated and the car's MPG will not follow the same curve.

 

I don't know how the car calculates how much fuel you are using. If it miscalculates, the effect gets magnified if you're only using half a tank as the starting point. I'd say let it to until it's nearly empty (don't worry, you can easily get 100 miles once the yellow light illuminates. Calculate it manually, since that is the only way to know exactly how much fuel is being used. I love computers as much as the next guy, but I think the car is only guessing on the fuel used.