Hello from Huntsville, AL!
 

Hey everyone! Long time lurker, network engineer, and "Rocket City" resident here. Sold my beloved 2004 Ram 1500 Quad Cab 4x4 and purchased my sister in law's 2004 Honda Civic Coupe LX Auto-trans (55,000 miles on it); because I do nothing but commute with my vehicle and my wife and I bought an SUV to accommodate the kids and tow the boat. The car was in decent shape, but not anything spectacular; needed a lot of mechanical love, some minor exterior love, and a deep interior clean. I'm looking to try to eke 40mpg (hopefully more!) out of this car and so far with some hypermiling techniques (neutral coasting as much as possible, some FAS, DWL, etc) I've been able to squeeze almost 34mpg out of this car (which is EPA highway) around town. My work commute is 15 miles of a handful of stoplights and some swoopy hills and averages around 40-60mph (I refuse to travel over 60 when I'm concerned with FE).

I'm concerned that something else could be wrong with the car and that's why I'm finding myself only able to currently squeeze out EPA HWY mileage while being so diligent with maintenance and FE techniques. I've changed coolant, thermostat, rad cap. Purchased an SGII. Checked, cleaned, and regapped spark plugs. Air filter replaced. All brake components from the lines to the rotors/drums replaced. Transmission fluid has been drained and filled 3 times now to bring the fluid up to snuff (Currently using Mobil1 Synthetic ATF, will change to Amsoil Fuel-Efficient ATF). Power steering fluid drained and filled 3 times with fresh synthetic fluid (there was notable PS whine when I bought the car). Tires aired up to sidewall max plus 5psi. I haven't changed the oil yet because my sister in law just had the oil changed with a synth-blend Valvoline before I bought the car and I just don't have it in me to change perfectly good oil atm. Once it goes to 60,000 miles (~5000mi from now) I'll change out to Mobil1 5w-20.

It's good to meet everyone!

EDIT: Where do I get one of those SWEET ecomodder signature images that displays your vehicle, MPG, percentage over EPA estimate, etc?!

Welcome to the site. I have little doubt you'll be able to get the Civic up to 40 mpg. Good luck with it!

Here is how to setup your signature:
http://ecomodder.com/forum/showthrea...ure-20941.html

You should have no problem beating 40 MPG in your Civic! Without hypermiling I was getting ~35 mpg. With hypermiling I was getting 39-41. And now with ecomods my current tank finished off at 44 mpg. And most of my trips are short 5-10 mile trips. Mine is an auto as well.

Got it. Thanks Daox!!!:thumbup:

That's so awesome. I'm doing hypermiling techniques now and I'm getting around 34mpg so hopefully I can use some of those sweet grille blocks, airdam, and coroplast wheel covers you've used to squish me above the 40 mark! I'm also going to remove the exterior rearview mirrors because Alabama law only requires a mirror that allows a view of 200' of highway behind the vehicle! :D

That's great that you're already matching the highway numbers on regular driving! Hypermiling takes time to maximize techniques and your cars quirks, so be prepared for those numbers to continue skyrocketing!

I noticed quite the improvement in coasting ability from the wheel covers, grille blocking, and fog light covers (you can view my Ecomodder build thread here). I haven't installed an air dam yet but will hopefully do that this weekend.

This generation Civic (mine, at least) seems to get the best FE at 36 mph, right when it shifts into overdrive. Best range seems to be 36-43 mph.

Ours are very similar with the exception of the coupe/sedan difference! I've noticed that my FE tends to maximize around 45-48. I've been able to coax TC lockup at low speeds too, which was a lot better than my 04 Ram used to! That sucker would absolutely refuse to lockup until I was doing 45mph.

Anywho, I'm going to get my hands on some packing tape to test out some grille blockage and remove the mirrors this weekend. I'll make a build thread and hopefully report back!

Prior to modding I wasn't able to consistently hit 50 MPG at 44 mph or above. Now with the mods and driving 36-43 mph (when safe) I'm able to maintain 50+ mpg on level ground.

Before modding I averaged 39 MPG with cruise control set at 55 mph. I haven't tested that since modding since I've rarely gone above 43 mph.

Packaging tape can ruin your paint, just like duct tape. I used blue painters tape and then covered it with colored duct tape. Painters tape is easy to remove (people with $10,000 paint jobs on their cars use it to protect their cars' paint jobs when taking their cars to car meets) and it doesn't damage your car's paint. And of course duct tape over it covers the ugly blue color. ;)

This car would never see that type of MPG with the cruise set. When I'm using cruise I'm averaging 29-30 per the SGII. However, I've only calibrated (and used) one full tank on this car, so the SGII may be slightly off compounded by my further practice of FE skills and I could see a bigger boost in FE by the time I go to fill up my next tank. I'm hoping my MPG is really higher than the SGII is giving me feedback on ATM.

Ah, good to know. I keep a pretty regular coat of Meguiar's Ultimate wax on all my vehicles so I'd rather not damage the paint. I'll be sure to do the primary adhesion with painter's tape first as you've suggested. Thanks!

29-30 mpg with cruise set at what speed? 29-30 mpg should be for cruising speeds like 80+ mph...have you had your vehicle serviced to see if there's anything there? When I bought my car I had a dragging brake caliper that made the first half of my first tank only ~31 mpg before fixing it. And when I had my timing belt changed along with the transmission and brake fluids, it probably added another 1 mpg or so. A dirty air filter can also harm FE, but those are relatively cheap to replace (I replaced mine for $8).

This car hasn't once seen 80. The highest it's gone is 65, but I keep it usually around 60 max. On average I'm doing 40-60 during my commute. I see about 29-31mpg with cruise set at 60.

As far as maintenance, I've performed the following:
-Flushed/changed coolant, rad cap, thermostat (180*)
-Changed transmission fluid 3X, each time about 100 miles apart, and replaced with Mobil1 Synth ATF
-Did the same to power steering fluid, replaced with Prestone Synth Asian Formula PS fluid
-Tires at sidewall max +5psi
-Full brake job including new drums, rotors, shoes, pads, lines, hardware and all sliding/contact points and pins properly lubricated.
-Spark plugs removed, cleaned, regapped to .044 per manual
-New cabin air filter
-Haven't changed air intake filter yet because the one in the car was still white and was supposed to have been recently changed, per the receipt from sister-in-law
-Haven't changed oil yet, because it too had been changed prior to my purchasing the car. Level seems a bit high though, tbh. Valvoline synth-blend 5w-20.
-Current tank has Redline SI-1 Fuel System cleaner in it because my sister in law never drove the car more than 5 miles (typically .5 miles each way to work) and she always bought cheap gas. So I'm suspecting that perhaps combustion chamber/injector deposits could be a possibility.

At 60 mph with cruise you should be getting like 37-38 mpg, flat road, no wind. Other than what I said I can't really think of what's causing your lower readous, unless maybe the O2 sensor is failing. I'm not a mechanic by any means but it seems that if it was an O2 sensor your MPGs would be in the 20s (but don't quote me on that). But your first tank is was almost 34 mpg? What did your Scangauge reading say for the tank before you filled up? It could be pessimistic/not calibrated correctly; honestly that's what I'm down to here.

Your maintenance is good so there shouldn't be a problem there.

Anyone else have thoughts? I confess beyond what I've said I'm somewhat befuzzled. These Civics should get in the thirties without trying.

I'm honestly thinking it's the SGII, which is why I'm really just trying to be patient with my numbers until the second calibration. The first reading was off by double digits worth of inaccuracy. I forgot to add that I've also replaced the wideband 02 sensor in the header and will be replacing the downstream 02 sensor this weekend. :) I really enjoy working on cars, lol.

If it was off by that much then I'm 99% confident it's the Scangauge. But I'm 99% confident about that mostly because I don't know what else it could be and I don't like not knowing. :D

Got any pics of your car?

I do, but I'll have to post them up once I'm at the house. I don't have my phone on me at the moment and I've got all the pics on there. I took a few after I got it tinted, but the camera is a little dirty so the pictures are a little hazy. The weather is crap right now here so once the weather clears up I'll take some nicer ones. I'll upload the older ones later today! :)

Here are the pics of "Sleek" as promised!

http://imgur.com/EXgOmFS
http://imgur.com/qvXwnTq
http://imgur.com/r1cD1vJ
http://imgur.com/Hxp4gjY

I was also able to add a pic of the car as my profile pic. Sleek represent! Lmao

Looking good!

Somehow I had a feeling your car was blue, don't ask me why. :D

BTW if you want your profile picture to show up as your picture when posting on the forum, set it as your Avatar rather than your Profile Picture. It's under "Settings & Options" in your User CP rather than under "Edit Profile Picture". Confusing, yes I know. :o

Done! Thanks man. Not very intuitive, but it works!

Update! Today (30APR18) I replaced the spark plugs, air filter, oil and oil filter. Preliminary testing showed a 4mpg improvement on the SG2. The SG2 still needs it's second tank calibration as well. Here's the info...

Sparkplugs: When I pulled and cleaned my plugs when I first bought the car, I removed and replaced them individually and didn't notice the "corona" burn on the porcelain because I kept them in the sparkplug socket. Some say this is normal, some say it's a failed seal in the plug. All 4 showed corona burns. I replaced the plugs unintentionally with the same ones that were in the car, NGK platinums. Holy cow are they expensive...~$15 per plug.

Air filter: Fram cheapo. Original looked clean, but now I know FOR SURE the filter is new.

Oil and filter: Oil on the receipt from when my sister in law had the car serviced before I bought it was Valvoline high mileage synth blend... weight unknown. Filter was carquest brand. This oil was supposed to have a little less than 1000 miles on it. When I drained it, it was pretty nasty. There was a LOT of visible wear metal and shine in the oil pan, which I always clean thoroughly before any change. There was even several pieces of metal that I could pick up and feel between my fingers. I've never noticed this in any other vehicle I've owned. It was concerning, so I'll reinspect at the 60k mile mark, which is a little less than 4500 miles away.
The oil was replaced with Mobil1 5w-20 and a Fram Ultra-Synthetic XG-7317 filter. Typically, I use Mobil1 filters but I'm doing a shorter than normal OCI for this first go around and didn't want to waste a $10+ filter doing it.

Everything seems to run a bit smoother. I'll report back after my commute tomorrow to let you all know if there is a noticed MPG improvement on my daily route.