fujiteam

I bought my '05 TSX in November and finally put in my third tank of gas today. On the second tank of gas I got 26mpg with a 200 mile high way stint. This last tank I pretty much commuted to work, which is about 7 miles, 50/50 highway. The weather got a little colder, but the car got a new air filter. My mileage dropped to 22mpg. I have beat epa estimates in both my parents cars on a regular basis and did not change my driving style. For the second tank I also moved the automatic to manual mode and had the engine shift to 5th earlier, around about 35. Could this be hurting the mileage?

Thanks

nj2pa2nc

give it a few more fill ups-

bmk04tsx

I can't explain your drop in MPG's but i've had my TSX for over 4 years and have always got around 26 MPG. Recently I changed plugs and installed a K&N filter and I am still getting around 26 MPG.

Simba91102

Ya, wait a while to decide if there's something wrong. Winter weather is a gas mileage killer, and I've found that adding even a little non-highway driving to the mix (I'm like 95% highway with my 05 and 07) can really pull the average down. I'm in CT too by the way, and though they get outstanding mileage on the highway (the TSX, and it can easily beat the EPA highway rating with reasonable cruising speeds), in my opinion it's kind of a pig around town (the way I drive anyway). Oh, and I'd suggest just leaving it in D if you're trying to watch your gas mileage.

mikw4

i too noticed a drop in mpg. purchased the car in sept and was getting 25-26 mpg. Now with winter it dropped to about 21-22. about 75% hwy driving. dont forget that fuel in the winter time is horrible.

jchan2

On the highway I can average 33 mpg if it's entirely highway (like I did today), but the city numbers (if it's straight city I normally get around 18) really tank the overall average.

So far on average I've been seeing numbers in the 25-27 mpg ball park with mixed 50/50 driving; it'll vary based on the balance of city vs. highway driving I am doing. Give it a few more fill-ups and see how things go...

LuvMyTSX

I agree on all counts. I had the same experience with mine. Highway mpg is usually very good, but around town, not so much. 7 miles is a really short trip (I used to have a 2.5 mile commute that killed my mpg).

JPSMAN

Fuel mixes are changed in the winter and the weather doesn't help either. I bet that mileage improves in the spring.

Jaan Lewaa

i m getting really low mileage nowadays cuz of i drive 95% in city n nowadays its extra low cuz heat is on almost all the time

808havok_tsx

i think the problem, including the winter weather in your case, is that your shifting 500rpms higher than the ecu is programed to. i believe the ecu errs on the side of gas savings and tries to shift right or a little before 3k rpm. it'll shift at around 4.5k rpm or so if you stomp on the throttle while in "D" mode. leave the car in "D" and let the car do the shifting for you if gas savings is what you are after.

but the car, in stock form, starts to comes alive after 3.5k rpms

nj2pa2nc

When I travel from NC to NJ and back I find I get the best gas mileage after I fill-up the gas tank at the WaWa in Fredricksburg, VA. (no matter whether I heading north or south). The gas mileage gets lower after I get it filled at the WaWa's in the Toms River area. Funny thing is wawa's contain 10% ethanol.

mrgold35

I usually average 24 mpgs combined on my commute and my wife get about 27 mpgs average when she drives the TSX. Our commute is about the same path (7 miles for me and 9 miles for her in the same direction). It goes to show how driving styles can affect gas mileage (conservative -vs- semi aggressive).

It could be a combination of winter fuel, commute distance, temps, and driving style. I don’t think it is a problem with the TSX.

fujiteam

Thanks everyone for your replies. I noticed drops in the winter in past cars, but this just seemed pretty huge. I think I was not clear about using the M mode. I meant 35mph and not 3500 rpm. In a 30mph zone I usually go about 35, which is just fast enough to put the car into 5th. So I put the stick into manual so I can get through the gears more quickly.

1Louder

I think you have the intersection of all the weather-related issues noted above, combined with the fact that the TSX is a very different car in the city as opposed to the highway when it comes to MPG. I'm a former hybrid owner with very efficient driving habits, and I still can't get better than 20-22 in the city.

So I think you're seeing the combination of weather, maybe fuel, and the car itself.

Also, having spent 2003-2008 monitoring every tank of gas in great detail (hybrid, then my TSX in 06), the one thing I've learned is that environmental factors like weather and city/highway mix put enough variability into mileage that trying to tell if if there is a difference using subtle techniques (like Manual vs. Auto) is nearly impossible. Because you'll never know if you did something right, or if you just had a tailwind that day.

Best bet is to just make sure the car is in good shape (tires, correct oil), drive efficiently, and wait for some warmer weather.