Hello everyone,

Lately I've been getting poor gas mileage on my 07 NAH. Mind you, I'm only on my second full tank of gas, and at about 680 miles. I've had the car since the day before Thankgiving (as you can see, I don't drive a whole lot).

I'm guessing it has to do with my driving route, but I'm hoping it's not a mechanical problem.

On my first tank of gas, I got approximately 460 miles to the tank. I averaged 25mpg or so.

I did a 1/2 fill up for my second tank so I didn't calculate the numbers there ( I didn't reset any readers) but I know the mileage reader was averaging low 20's.

At around 660 miles on the car, I put my full 2nd tank of gas in. After I reset all my numbers, immediately, my mpg range only went up to 380 miles (and it has not gone up). This seems awfully low considering on the first tank the car read in the 500+ range.

I've only put 60 miles on this 2nd full fill up, and I'm averaging 22-25 mpg.

My driving habits: I drive about 5-7 miles a day (2.5 miles one way to work, and add in any errands ran at lunch or after work).

I know this isn't alot. My car normally kicks into EV mode during the last leg of my trips (a mile or so). I do notice that when I'm in EV mode is when I get to the upper 20's in mpg. I have yet to see anything over 30 (except during my first tank, but it was low 30's).

The weather is cold here in Cali (high 40's, low 50's - yes I know - warm compared to most places). I'm guessing my mpg suffers in the morning due to the car not having the 10-15 minute warm up period after the coolant light goes off. I'm hoping this changes in the summer. I should be in EV mode more then.

Anyone have any thoughts, or pretty much agree?

Thanks,
Sarah

 

I would bet that your poor mileage is almost entirely due to the short 2.5 mile commute (although that works in your favor as far as fuel consumption is concerned). I think I usually average high-20's for the first couple of miles on a cold engine, but I have seen as low as 21mpg (in 0 degree weather) on my own 6.5 mile commute.

If you want to rule out a mechanical problem, try a longer test drive (say 25 miles, on suburban or light-traffic city roads). At average speeds between 35 and 45mph, where you can take advantage of EV mode, you ought to see mileage numbers in the high thirties or above. Under those conditions, I usually see 45mpg.

 

I'm in Northern California and I'm seeing something similar, but not quite so bad (around 27-29). I get pretty bad gas mileage on my 15 minute commute in the mornings BUT, when there's traffic, I get much better. I also notice my engine coolant is too cold light come on in the mornings during the first part of my commute. I wonder if we can install an EBH like the prius owners to help with this? I'm guessing the short trips in the cold are killing your gas mileage.

 

You are correct. It is a combination of both the short commute and cold weather. Last winter my wife drove our Prius to work (only a 3 mile commute one way) and our MPG saw a significant reduction from when we would drive on the interstate for long periods of time. But, this past Christmas on a trip to WI, despite we were on the interstate the 16deg temp. outside caused our mpg to drop from the typical 50's to 20's... I thought I was going to cry! Also, I don't know if anyone else has experienced this but, we are actually getting better gas mileage with more miles on our car. I don't know if there is a logical reason for this, but I am sure someone out there would know. Anyway, don't give up yet... You just need better conditions.

 

We've gone up and down on this. We typically get 34-36... and then out of the blue two tanks dropped to 25 mpg. We couldn't find any reason.

Now, we are very careful to fill up with only tier 1 gas... and we avoid the station where we got the two 25 mpg tanks. I don't know is this is fact or myth... or why our MPG changed... but we are back to getting 34-36 mpg.

 

You are breaking the car in. More miles should deliver better gas mileage.

 

You hit the nail on the head. The car just needs to be broken in. An oil change will probably help because it removes the tiny metal particles.

 

I don't know if this is hitting the nail on the head. We got 34-36 MPG out the gate when the car was brand new. We got 34-36 MPG average on all our early tanks.

 

Hmmm... Well my first tank is running 33.9mpg as of right now, so that seems to be pretty close, as the first 250 miles were highway. I've heard it only gets better after break-in and an oil change. I could be wrong though, since this is my first hybrid.

 

I heard about how things were going to get magic after "break in" too... but we never saw any difference. I think it is 95% myth.