Itchytoe

Supercharged? No, you won't get enough boost for it to matter. When I say high boost, I mean high even for a turbocharger. Your SC won't be nearly enough boost. You could run regular with a SC.

gotmilk9579

I've got a 2004, 5AT, and also wondered why such horrible gas mileage.

Combined it's typically 23 mpg. On a highway trip averaging 75-80 mph I can get up to 27, but that's not typical. Most recent trip this weekend I averaged 65 mph and got around 25 mpg.

dallison

We get around 25, but we have heavy feet.

nigelboyne

well said mate when i run on 95 octane i only get average of 25/26mpg when i run 99octane the highest here in ireland i get 28.5/31mpg and this is all taxi driving in dublin, as i have said before fuel quality and proper oil changes along with semi to fully synthetic engine oil is the life of these hondas, i recently checked the valve clearence and there is not a millimeter of play on the chain.all the valves springs cams etc look like new as if all components had baby oil all over it no wear what so ever roll on the next 250k

davidspalding

How well do you maintain it? Barely according to the manual, according to the manual, or better than the manual?

For one, the manual's recommended spark plug replacement is about 25,000 miles later than some recommend for the Iridium plugs that are installed. Likewise engine air filter, I change it every 6,000 - 10,000 miles. Tires, are they rotated and balanced every 6,000 - 8,000 miles? Do you check inflation weekly or semi-monthly, are they at the door jamb sticker recommend PSI? All these things can effect mileage, just a wee bit of course, but they can pile up.

FYI, Consumer Reports did a mileage test, they found that every 1 MPH over 55 started a slight decline in fuel efficiency. So I wouldn't expect great MPG at 80 MPH. In fact, my own month-long experiment in driving 60 MPH to and from work showed increased MPG ... but also increased frustration during the commute. I went back to doing near the limit, Steady Eddy speeds, which isn't easy with all the cell phone talking and breakfast eating goofs in my urban area.

GwinTate

My 04 TSX has 88k miles; I've always gotten about 29 mpg combined. If I take a long "road trip" on the turnpike, I average about 32 MPG. Just city driving I'm about 27-28 MPG.

Devil Dog 21

My wife's 05 TSX has 51,000 miles on it and gets 25 mpg combined. She also has a lead foot, so I'm sure it could be a few mpg better.

davidspalding

I'm green with envy of some of you guys with such low mileage. My gosh, Devil Dog, your wife's car averages less than 10,000 per year of operation!

04tsx5at

I just became the proud owner of a 2004 TSX w/ 5 AT. When I made a 400 mile trip shortly after purchase I averaged 32mpg on premium which in Ohio is 93 octane.

Audioserf

Supercharged 6MT 04 with 68k on it here. My driving is primarily around town and stop-n-go traffic. I pull around 270-280 miles out of a tank before the idiot light pops up. On longer trips I can get around 400 miles out of the tank, cruising around 70mph. I don't do math so idk what the mpg is. I would deem it "bad and dumb".

dumdukus

I have 07 TSX , my gas mileage is about 30-33 , but its mostly freeway since im commuting to work a lot. Only city I will get about 24-27 and car has 113k miles on it.

CarbonGray Earl

My MPG sucks (20.0 to 22.0), but its because most of the driving I do is in town. And my town is notorious for traffic.

...well, I guess i should also add that my MPG sucks because its in-town and I do hit a reflash-enhanced redline once or twice each drive.

calisoulsurfer

Honestly I have to say its mostly due to driving style, and other factors you can't control.

My 04 with 161K gets about 16 mpg in the city here in Flagstaff, AZ, but I live at 7K feet, and this is more stop and go traffic than NYC. When I lived in Savannah, GA I was getting 20-22 mph in the city.

On the flip side, I recently drove through the mountains from Denver to Flagstaff with a car fully loaded down with stuff (I was moving) and still got 34 on the highway.

Dach Savage

Hi all, I recently acquired a nicely kept `04 TSX auto trans with 135K. Driven it for a couple months and after checking mileage for 2 weeks looks like 20-21 mpg with 70 - 30 highway city usage. I have been running regular and the car seems a little "poochy". I have noticed that the high octane fuel around here (Phx) is 25-40 cents higher than the 87, would consider running the premium fuel if it made a worthwhile difference in performance and mileage. I could use some advise on what to upgrade in order to get a little better mileage and performance without breaking the bank. When I first got the car I checked and cleaned the air filter and did oil change with Valvo red bottle hi-mileage oil, about due for an oil change. I plan to change the plugs this weekend but not sure what brand / style is working best in these. Thinking of installing a cold air intake and (due to the mileage) a hi flow catalytic converter but could use recommendations on what brands are the best bang for the buck. I have found a cold air intake kit with "dry" filter on Ebay for about $60 bucks and others that look pretty much the same ranging up to about $300. I havn't priced converters yet, still searching for recommendations on these. I put a Magnaflow on my Dodge PU and it made a ton of difference in performance. Would like to stick with bolt on type mods and don't want to put more money into the car than its worth but I would consider an exhaust / muffler system change if it would add a reasonable amount of torque I would call the performance level I am looking for as "sport / touring" without sacrificing mileage. Also wondering if some type of performance chip or re-flash would be advisable / worthwhile considering I am just upgrading the intake and exhaust flow and otherwise keeping things pretty much stock? Sorry for the newb questions but this is my first Honda upgrade project. I have a `96 Del Sol that (until I popped a timing belt) seemed to be a lot more peppy stock than this TSX but had knee surgery and need an auto now. Thanks - Dach.

horseshoez

iTrader: (2)

A few comments in no particular order:

• Check your Owner's Manual for the correct spark plugs, if you don't have one you can download one from the Acura Link web site.
• Your mileage does seem rather low given your 70/30 Hwy/Urban mix.
• Running Regular gasoline will most likely result in lower fuel economy.
• A new/clean air filter, or even a low restriction air filter, or for that matter, no air filter at all will not help your fuel economy improve. In fact, per a very exhaustive EPA study from a few years ago, modern fuel injected cars get slightly better fuel economy with a highly restrictive air filter.
• High mileage oil will be of no benefit; just use what is recommended in your Owner's Manual or any high quality 0W-20 synthetic oil.
• Similar to the whole air filter thing, using a high flow exhaust and/or catalyst will not help improve fuel economy.
• A reflash will not do squat for fuel economy on a normally aspirated engine.

TexasHonda

If you have a scan tool, check Long Term Fuel Trim (LTFT). If > 10% you need to find out why; fuel injectors, air leaks, lazy AF sensor, etc. A new AF sensor will cost less than other stuff you've considered and may actually do some good.

For instance, intake air leaks are corrected by fuel control adding fuel (more fuel to balance A/F mixture to ideal).

good luck