Hello from Huntsville, AL!

[westb87]

Originally Posted by mpg_numbers_guy

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.

[mpg_numbers_guy]

Originally Posted by westb87

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.

[westb87]

Originally Posted by mpg_numbers_guy

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.

[mpg_numbers_guy]

Originally Posted by westb87

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.

Got any pics of your car?

[westb87]

Originally Posted by mpg_numbers_guy

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.

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!

[westb87]

Here are the pics of "Sleek" as promised!

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

[westb87]

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

[mpg_numbers_guy]

Looking good!

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

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.

[westb87]

Originally Posted by mpg_numbers_guy

Looking good!

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

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.

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

[westb87]

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.