xs0ysaucex

So I just filled up my tank 2 days ago and after driving 100 miles(freeway/local), I am down to half a tank. What the hell is that? I notice my gas milage has been awful lately. In addition, my maintenance lights started flashing when I turn on the ignition. It has been down that for about 3-4 weeks now. Anyone has a hunch on whats wrong? I have a CAI and XS headers? Could it be my headers thats causing this or something else in regards to emission? My car is an 03 tls w/ about 105,000 miles. Any help would be good. I was thinking about taking my car for a diagnosis, but I kind want to avoid spending that much on just a diag. Thanks.

01tl4tl

maitenance light = time for oil change= 7500 since you last reset the light
105k miles is due for tune up- plugs timing belt water pump
Have you seafoamed?

headers and cai will kill mileage,,, especially when you are enjoying them~
check tire pressures
check the spark plugs
Tune up

xs0ysaucex

Yea all the maint. is done. and thats why I am like what could be wrong. I dont race or even push the car so as far the gas consumption I am clueless!!!

totaledTL

Faulty oxygen sensor(s)?

eleventure

gas leak??

fsttyms1

What plugs did you use? Tire pressure? Gas used? You may have a O2 sensor thats not working as it should.

You also say you drove city/hwy.. How much of that is actually HWY and how much of that is giving it hell?

Also CAI and Headers WILL NOT reduce mileage UNLESS you have your foot to the floor to feel the power they are making.

Bob_F

Do you ever leave your TL where someone could siphon some gas out of the tank? That may be a longshot but gas theft increased significantly when the prices skyrocketed earlier this year. I actually have a locking gas cap on my TL now.

And, as mentioned above, how much of your driving is "city driving". That can make a huge difference in TL MPG.

Finally, calculate your true MPG by keeping track of the miles you've traveled between complete fill-ups. That's easy to do.

01tl4tl

kris- I meant headers and cai reduce mileage because: who puts that on- and tries to think economy driving!?!?

grip

i did....a TL is a slow FWD sedan no matter what you do. i want my TL to get decent MPG, and be comfortable...your a fool if your trying to make a TL fast.

i did an intake, and exhaust to get better gas mileage...a $15 fuel filter helped MPG the most though.

totaledTL

Replacing a fuel filter isn't going to increase your mileage- something else was going on.

grip

sure thing....

xs0ysaucex

I have denso irdiums replaced about 10k ago, so I know that shouldnt be the problem. Pretty much the problem I am having has nothing to do with regular maintainance or upkeep of the car because I definitely take care of her.

Im positive no one is stealing my gas and I dont ever floor my pedal. haha.

So right now I am 175 miles so far on the tank with about a 1/4 tank left. (it was a full tank) I disconnected the neg. batter cable to see if that could do something, but as mention from another post above CAI and headers will not affect gas consumption except flooring pedal.

So far the o2 sensor could be the culprit or a gas leak? Is this gas leak internal or external your are guessing about, eleventure???

kakins23

Brother I stumbled on to your thread glad i did, I'm suffering from the exact i mean exact problem. I have done it all,seafoamed,alignment,oil,air,throttle body cleaning cabin air(that was a great thread) the list goes one, tell me you have figured this out. I think it's a faulty o2 sensor that is not coming up as a code. Not sure how this happens but i guess its possible. Man let me know if you have fixed this problem or what!

Flipster23

iTrader: (15)

CAI helps with the gas we were talking about that at our last meet. I had a CAI in my civic took it out and noticed that my gas went down a little quicker

fsttyms1

Is the driving all city and short trips? If so thats probably the problem and there is nothing wrong with your car

rob-2

I've grown to hate threads like this... 'miles to half a tank' maybe your guage is off...

tell us mpg and type of driving, approx shift points, and modifications. Anything else you think is of note is fair game to mention too.

fsttyms1

totaledTL

Unless you calculate your mpg it's pointless- like comparing apples & oranges.

newperson

iTrader: (2)

Is there an easy way to measure "power" & acceleration though? With the problems I have, I hate having to use previous experience as my reference. I average about 16.5-17mpg. 90% city though which I guess makes it seem less worse.

fsttyms1

Only way to measure that is a Dyno. How high do your RPMs get before it shifts, that will give you a better idea of how much power your using. Those that dont accelerate quickly and dont let their RPM go much above 2500 rpm are going to get much better RPM than those that let it get to 4k before it shifts.

rob-2

I think you mean better MPG.

kakins23

So will resetting my ECU help. It just plain sucks that some people get 350 and other get 200/250 there has to be a solid reason besides driving habits. I've been doing more hw driving and still have'nt gotten 300 hundred.

rob-2

Not likely, but you can try.

Fastest way to save gas is drive slower and be lighter on the acceleration.

kakins23

Thats the thing. I'm not typically a fast driver,my car I think is pretty well mantained. I have even had my fuel pressure regulator replaced. Just saying that to say I just expect more from this car If I drive for a while I can see my gas deplete in front of me. Acura checked for gas leaks. NOTHING

rob-2

Do a test, drive in d5, and dont go above 2500 rpms. On the freeway do no more then 70mph. If you dont get 22-26mpg mixed driving then somethings off.

If you're getting 18mpg city, everything is fine.

Straight highway (NO CITY) expect 28+

Got rims, or anything done to the motor expect a drop. It's really simple.

Everyone blames the car, but it's really a problem between the seat and steering wheel. (Quoting someone else).

I grow tired of this....

Flipster23

iTrader: (15)

I get about 310 now and that is mixed city and highway.

rattmann316

check the thermostat?

newperson

iTrader: (2)

I shift around:
~2.75-3k, ~2.75-3k, ~2.25k, don't know about 5th since 4th is usually as high as it goes.

I'm a pretty conservative driver. I'm not concerned about my MPG (well, not to the point I feel it's an issue)...I used to only get around 14mpg in my old car (Chevy Malibu) so this is a big jump up. What I'm more concerned about is that it doesn't accelerate like it used to...unfortunately I never did MPG tests during that time or paid much attention to the shift points (which was 2 months ago).

kakins23

Gonna fill up in Jersey tomorrow, my tank is almost empty now. I will record how many gallons it took to fill then report back! also I will drive in d5, and wont go above 2500 rpms. On the freeway I wont go more then 70mph. as rob-2 suggested.

TLP_TLS

i thought we had internal fuel filters??.... i could be wrong. someone advise

fsttyms1

We do. Its an internal filter. There is an external filter on the Evap system but that wouldnt help mpg

TLin401

6 month revival

I don't understand why people revive these threads.

totaledTL

Because he's pitching something he's selling.