TL|GTX

dont accelerate hard, and drive slow, and dont brake hard. And use 93 octane gas. And dont have ur car always loaded with junk, just putting more weight on the engine.

velik26

sell it and buy a civic...

rockstar143

iTrader: (6)

^^^that seems kind of obvious and a little impulsive. I think a TL is nicer than a civic.

triton2k3

does 93 octane really help? only reason I ask is because i asked for super today at a sunocco and the guy gave me ultra which is 93 octane. I'm getting 29 mpg which is 3 to 4 mpg better than usual. Just curious if I'm crazy for thinking it was the gas or it was one of the other 15 things that possibly factor in on mpg.

SouthernBoy

Your engine was designed to operate at its maximum efficiency on a minimum of 91 octane rated fuel. This means that the ignition timing and amount of fueld delivered to the cylinders will be managed to produce the most advance needed for throttle opening, load conditions, ambient temperature, and driving demands. In other words, your engine will be doing what it is supposed to do as per its intended design. When you use a lower octane fuel, the ECU must compensate for this change, so it retards timing and reduces the fuel shot accordingly. This means less power.

To the driver, this means that for his normal needs, he will now have to use a slight increase in throttle opening and do this longer to obtain the desired speed, so more fuel is burned. This is essentially why your engine will get lower fuel economy with less grades of fuel.

triton2k3

well done. couldn't have answered that better. Thank you

I hate cars

There's not a lot you can do besides using common sense and premium gas.

You're accelerating a 3,600lb car and doing short trips which means thicker oil and richer AF mixtures. Take it out on the freeway and you can nearly double the mileage.

SouthernBoy

As I mentioned before, I once managed 27.98 MPG for a week of work commuting in my '04 manual TL. This was in the hot summer months. I did not run the A/C for that week. My commute is almost all through residential and small city streets with the usual mix of stop signs and traffic lights. Mornings I go in very early so I see very little traffic. But in the afternoons, the traffic is moderately heavy for that area (which means a couple of light cycles with stop and go).

The car was still pretty new when I did this and had the EL42 tires. I have never tried to get that kind of mileage since then.

hyperspeed

as of right now my car has about 209.7 miles with a little bit more than 1/4 tank of gas left since i posted the thread.

1995hoo

Regarding octane: Most of the Sunoco stations around here sell four grades (87, 89, 91, and 93), with 91 typically costing 2¢ a gallon less than 93. (The top two grades used to be 93 and 94, but the latter was phased out due to environmental concerns relating to MTBE.) I've compared 91 versus 93 many times in both city and highway driving and have noticed absolutely no difference in the TL's performance, so I generally opt for the 91 now at the Sunoco. Doesn't save all that much in the scheme of things, though; on average right now I'm filling up twice a month since I'm not presently commuting, so if you figure 15 gallons per fillup, it means I save 30¢ per fillup, 60¢ per month, $7.20 per year.

The fuel economy difference between highway driving—and by that I mean true highway driving at or above the speed limit, long-range, steady speed, in sixth gear—and city driving (including stop-and-roll driving on I-395 here in Virginia) is astonishing in the TL. When I was commuting to downtown DC my typical average fuel economy per tank was around 18 to 19 mpg for most of the year (somewhat better in summer when Congress is in recess, considerably better around Christmas when everybody takes the week off, and somewhat worse in late May/early June when people seem to commute earlier in the morning). But when I travel any distance on the highway I routinely average 30 mpg, even when my average speed exceeds 70 mph. My record number of miles on a single tank is 455, going from Portland to the last exit on I-78 northeast of Harrisburg (probably could have gone farther but I didn't want to chance it as my yellow light had been on for a while; also could have gone further if the Cross Westchester Expressway near White Plains weren't such a mess, which slowed me down and screwed up my mpg average).

It's an exercise in futility to try to realize any MAJOR improvement in your fuel economy in average city driving. The best things you can try are to avoid jackrabbit starts and hard stops and to run your TL in the highest gear feasible for your speed—that is to say, lower revs in a higher gear are preferable to higher revs in a lower gear unless the higher gear would cause you to lug the engine or unless you're in traffic that would require you to shift down constantly anyway (in which case leaving it in the lower gear and not shifting tends to be the more efficient option).

velik26

It is an answer on the question.

Who argues about it?

I hate cars

That's amazing for stop and go. I guess it would be easier with the manual to get the right combo of acceleration and fuel cut deceleration. With the auto at moderate speeds, you let off the gas and the rpms go to idle, using an idle amount of gas.

SouthernBoy

I have never tried to duplicate this since then. But I ran the test for a week of commuting and used the tried-and-true method of factoring the results. I even filled up both times at the same pump in the same position and after auto-shutoff, round to the nearest 5 cents.

I know I could not do this again now since I have the Michelin Pilot Sport A/S Plus tires on my car along with 68,000 miles with OEM plugs, cats, and such. But I don't really care anyway. It does well and I'm still pleased with it. That week, I was really trying to get the most out of each gallon.

billycuth

has anyone ever tried this?

http://cgi.ebay.com/ebaymotors/REAL-...lenotsupported

hyperspeed

i think if it works it should worth more than 23.99 lol!!

jeowen

+1

ballerjai

12mpg city FTL!

Our car isn't so great on city miles, but it's pretty killer on the freeway.

I hate cars

Interestingly I've found that by accelerating too easy, I end up using more gas. Probably due to the fact that it's an auto and the convertor is much more efficient at higher rpms. I think I was turning a higher percent of my power into heat in the convertor accelerating too easy.

Going down the big hill here, I've kept it in 4th with my foot off the gas for literally 10-15 minutes at a time and watched the miles to empty count backwards.

rockstar143

iTrader: (6)

count backwards being that it's adding miles?

I have too!
If I coast on the highway it'll either start adding miles or just stop deducting.

o4Komodo

iTrader: (2)

I get 700km+ per full tank on highways.
Lately my mileage has been fluctuating from either 6L/100KM or 7L/100KM.

For highway driving I find that... getting up to the speed you want quickly [but not too quick] and maintaining that speed through out your trip gives best results.

ray-ban

Take the bus?

LaCostaRacer

I wonder how many people complaining about poor gas mileage use drive thrus frequently? I normally don't use drive thrus but had an urge last night for an In&Out burger after coincidentally just filling up my car and resettting the MID. I drove about 2 miles prior to the In&Out run with the MID reading 18mpg before entering the In&Out parking log. After 10 minutes in and In&Out drive-thru queue the mpg dropped to 8! By the time I got home (8 miles), I was just over 15 and I normally get 19-20 on that commute. I'm not saying Drive Thrus are the only factor but they don't help your MPG either.

I know some people who only use drive thrus and often, so I could see how their mileage would suck. When you're idling in a drive thru or lots of traffic lights you're getting zero MPG. The more you're idling the worse your mileage on any conventional car.

Johnny_b

wtf are you talking about?

In English. Stop mashing the gas pedal. You'll get better gas mileage.

robocam

A car barely uses any fuel at all at idle.

It's very easy to test your hypothesis. Just try a tank using drive thrus and try one by shutting your car off and walking-in to order.

I'll bet that there will be no significant difference in fuel consumption.

SouthernBoy

I'm sure you're right about this. That and the parasitic loss is greater through an automatic than a manual. When I was doing this, I was VERY cognizant about my shifting and shift points, but I never lugged the engine (never do that anyway). The car was still rather new with fresh factory rubber, plugs, and a nice clean intake (specifically the throttle body, manifold, and plenum.. not to mention the valves. Later I easily managed over 26 MPG on the same commute without any special techniques and also using the A/C when needed. The best during those tests was 26.391 as I recall. The Michelin Pilot Sport A/S tires I had installed in the spring of 2006 were the replacements for the OEM EL42's and I quickly noticed increased roll resistance (my car would not coast backwards on its own out of my garage like it did with the EL42's). My commute mileage dropped into the 24's and my highway mileage dropped from a high of 33.94 (with A/C running the entire time), to a little over 32.

LaCostaRacer

In Simple English I'm saying that people that leave their cars idling for extended periods of time will see a degradation in gas mileage. They may frequent drive thrus or they might like idling their cars talking to friends and neighbors on the street. I just pointed out a real-life example of how a 10 minute drive-thru idle session affects on leg of my average commute in the car. Some of you might do the drive-thru thing every single day or idle unnecessarily for other reasons maybe.

I don't care how little gas your car is consuming when it's idling and the TL has 6 cylinders needing fuel- the car is getting ZERO MPG when idling. The more you idle, the worse your mileage. Since hybrids automatically cut the motor and delay using the motor (via electric motor) they can get much better mileage than a CONVENTIONAL vehicle.

You can do a search on my login and see that I actually did an experiment with cutting the engine off at traffic lights less than a year ago. It yeilded a 1-2mpg improvement but I concluded the excess wear/tear on the vehicle wasn't worth the savings.

I think I'll be ignoring these gas mileage threads in the future since we always talk about the same stuff and the OP rarely gives any meaningful data (like average MPH from MID)- just a statement of fact that they are getting crappy mileage. The MID avg speed explains what's happening regarding the owners driving environment.

I would bet that anyone with a < 25MPH MID reading exceeds 20 MPG. If your MID reads lower then your mileage will reflect it and be lower. The TL is a very efficient vehicle on the highway but the mileage will suck in the city like most other 6-8 cylinder cars will.

Adios Amigos!

jnc2000

my mph averages upper 30's low 40's... With that I'll see anywhere between 28-33mpg on the MID, 28-32mpg actually calculated. If I happen to be doing a lot of city driving, I'll usually see my MID report an average MPH less than 30, and a mpg between 24-27 actually calculated mpg is right around there.

bruce.augenstein@comcast.

Assuming you are driving a stick, what you should do is to use very low shift points - no more than 2500 rpm on the one-two, and progressively lower rpm as you get to the higher gears. Your goal should be to reach the next gear at a point just barely above lugging. Note that lugging absolutely will not harm your engine, but it's annoying.

Contrary to popular belief, you should use the maximum possible throttle - consistent with smoothness. That will generally mean at least 50% throttle in first gear, graduating up to 100% (or near 100%) throttle in fourth and fifth. Actually, full or near full throttle in all gears would be best, but it's nearly impossible to do that in first gear while shifting at no more than 2500 rpm and maintaining smoothness. If you don't care about smoothness (meaning you have no passengers), then by all means use full throttle even in first gear.

Shifting at minimum rpm lowers overall friction, and using max throttle lowers pumping losses, making for best possible mileage.

On the highway, coast whenever the opportunity arises. Your TL shuts off the injectors when you are coasting in gear against engine compression.