What am I doing wrong?? 2005 Civic EX Auto

[CoronaWithLime]

I've been getting between 22 and 24mpg pretty consistently lately with this vehicle. I am doing 90+% city driving. I am regular with oil changes and the tires are inflated properly and only about 10,000 miles old. The car has about 55k miles on it.

I've tried going to different fuel stations, always use regular fuel. I am very conscious about conserving momentum.

The one thing I can think of is that I am running the AC a bit lately (95+ here in Alabama!!).

Does running the AC on full vs. the lowest setting make a difference or does it use the same amount regardless as long as it is operating?

I love this site! Thanks so much for reading!

[xbUser]

I think you need to tell us more, like
1) What does it mean 22-24mpg consistently LATELY? Does it get better mpg before?
2) What is the reading for your tire pressure? Most people says 30psi is inflated properly. Hypermiler would say at least the max psi (usually 44psi). Some drivers push to 50 to 60psi. (I don't recommend higher than that)
3) What is your tire model? Low Rolling Resistant tires saves more gas than performance tires.

Besides tires, did you clean up your trunk? Are you driving auto/manual? If you drive with auto, are you driving with D4? or D3?
Running AC with full setting hurts more than running with lowest fan level. Imagine you need to provide the same cool temperature with higher air flow, you need to do more work, right? Other thread also shows that affects mpg. Usually, open the window <40mph is more efficient than using AC. If you have to use AC, turn the fan slower.

[saunders1313]

Also would need to know what techniques you are using. Do you coast up to stops, engine on or off? Do you idle at stoplights? etc.

[CoronaWithLime]

I was getting a solid 28-30 when I lived in Georgia. I have a suspicion that the gas here in Alabama is of inferior quality.

My trunk is empty except for a picture of my ex girlfriend that I plan on using as motivation to get those lug nuts off if I ever have to change a tire.

I drive automatic on D4 at all times.

I keep my tires around 35, but I will defiantly give 40-45 a shot. I will get back to you with the tire type.

I do coast to stops and I've found it very useful to brake a bit harder in the beginning - i can usually avoid having to stop entirely at traffic lights out here in the burbs.

I am able to keep my car in neutral about 20% of the trip both to and from work each day (about a 6 mile commute each way).

I put my car into neutral when I am at a red but leave the engine running, so the RPMs drop a below 1k, they seem to stay around 1200 if i leave it in drive and just hold the brake.

Again, thank you so much for the prompt responses! It says a lot about this community and the people who kelp keep it running!

[saunders1313]

Since you do a lot of city driving can you shift to neutral and then shut the engine off when coming to a stop? This does help quite a bit. Have you tried Pulse and Glide?

[azraelswrd]

-Corona

If nothing has changed in terms of equipment and driving, and only in fill-up location then it is not a leap that the new gas is not as pure as what you were using before. I've read enough reports that gas with ethanol added is less energetic than just pure gas.

I always try to go and refill at the same station. Look around and see if there is some sign that says "Up to 10% ethanol". I believe states are pushing for mandatory notification (which means not all pumps say if they have E# or not).

If there's nothing wrong with the gas, then it could be something else in the engine. I won't pretend to be a mechanic but when was the last time you had the car/truck serviced?

Yes, heavy A/C usage will hurt your fuel economy. If you must use it, the best way is to use it only on highways and in short bursts with the air on recycle. Turn off the A/C once you feel cool enough. Turn it on once the heat gets too unbearable. At slower speeds, windows open will be better as the drag won't be as bad. Full A/C vs low A/C is a slight difference but it depends on the specific parts in your vehicle and how long you're running them. Not all compressors were created equally.

If you had some way of seeing your instant MPG or gallons/hr then you'd know for sure which way is better or worse. Assuming you're in the 2005 Civic, a scangauge can fulfill this need of instant feedback.

[CoronaWithLime]

The one thing I'm worried about is the wear on the engine/starter from stopping/starting it every time I'm at a light but I am definitely willing to try it at one of the longer lights on my route.

I practiced Pulse and Glide today actually, but need to find more places that it is practical for me to do so.

[Blue07CivicEX]

55k seems a little early but possibly new spark plugs, fuel filter, air filter. Is the car running rough at all?

With a Civic and with mild hypermiling it seems like a hardware issue (car isn't functioning well). I would start with the basics I listed above and work your way into the scarier stuff but 22-24mpg in a civic when you're actually TRYING to get good mileage seems WAY too low for it to just be your driving habits.

[azraelswrd]

Engine off at lights if you know it will take longer than 10 seconds. Someone did a study that said restarting a gas engine was equivalent to 6 seconds of idling. Otherwise, shift into neutral and idle.

Practice P&G in an parking lot if there is one near you and a road is not available. Also remember that not all automatic transmissions like having the engine off while you shift into neutral. Check your owners manual just to be safe.

Mostly city eh? I don't know if P&G will be all that useful (unless there are that many opportunities for coasting). I just go with most pulse-n-gear coast to get the benefits of the deceleration fuel cut off. My current MPG is into the 40s thanks to that.

If you haven't already done so, check over the 100+ tips to make sure you are doing everything you can.

[rjacob]

Originally Posted by azraelswrd

Engine off at lights if you know it will take longer than 10 seconds. Someone did a study that said restarting a gas engine was equivalent to 6 seconds of idling. Otherwise, shift into neutral and idle.

I have wondered, does this include recharging the battery for the drain of the starter motor which just drew a bunch of amperage?