I am still continuing to see what keeps my MPG lower on 2005 HCH than expected. As others expected the oil change to Mobil 1 (0-20W) did not make a noticeable difference from Honda oil. I now have eliminated several variables that have not made a difference. Even though it is hot I tried AC off for a while on the highway, and that also was not a large factor in mileage averages -- now avg. is 36.5 to 38 range on highway for short trips of 40-60 miles. In town we have achieved about 40-41 with AC on.
Here is a possible clue - while going 65 mph I notice on relatively flat terrain I could work up to approx 75 instantaneous at approx 1900 RPM ... but it was extremely hard to hold and then with even the slightest hill it would drop to 25 MPG instantaneous under all possible gas pedal positions YET still was about 1900 RPM -- then it was difficult to get above 50 and back to 75 MPG ... then back to 25 where it loved to reside. That process gives the low average of upper 30's.
Hard to imagine a 1.3 Liter engine getting 25 MPG. The battery level dropped fairly low also during the time I was observing this process.
Can a sluggish O2 sensor cause such excessive fuel use, and not cause the check engine light to come on? Or any other suggestions?

 

It is actually a 2006 HCH for my note above -- typo ... sorry.

 

As to the issue of proof, you can find pictures and even videos of high mileage vehicles here and elsewhere on the internet.

As to how it is done....

It may not be possible for everyone, depending on their local conditions. Worse case scenario, a big, cold, rainy/snowy, windy, hilly city with stop signs at the bottom of every hill, lots of traffic, aggressive drivers and a short commute. There is no reasonable/safe way for anyone to get record breaking results in such conditions.

On the other hand if someone lived in a warm, dry, calm, area of sparse population with light traffic and a fairly long commute, amazing results could be achieved (with some effort).

 

I tend to believe the claims that folks here are making. I only have an elementary knowledge about how to exploit the car's strengths and am consistently above 50 mpg.

Truthfully, I am a little frustrated because I don't seem to be able to get over the proverbial hump. I can get 50-53 mpg with no effort, but I don't seem to be able to consistently have trips above 55mpg and when I do, I can't seem to replicate it with any consistency.

 

Ahhh... time to elevate your HCH-II skills to the hypermiling level

Cheers;

MSantos

 

...

 

All one has to do is read Tarabell's article and follow the basic steps of Hypermiling:

1. Pump your tires to max sidewall = 44psi
2. Slowly accelerate
3. Drive like you don't have breaks
4. Drive the speed limit or a little slower
5. Slow down to or coast to a stop
6. Don't drive w/ your windows down
7. Use little or no A/C
8. If the Autostop doesn't kick in at a stop, shut her down anyway.
9. Walk in to order your fast food, don't sit in the drive thru

You have to be 100% dedicated. Ignore all negative reactions from other drivers, especially the ones behind you.

Before I bought my HCH II, I was a pretty aggressive driver that didn't mind speeding, but I changed my tune when I bought this car.
It's been a year of reading about Hypermiling and practicing it and now I'm disappointed if I don't hit a least 60mpg in my 33 mile daily commute. Some days I'll hit 69mpg and my best commute was 74mpg. And I drive in moderate commute traffic with several stop lights ( I purposely avoid the interstate ).
Driving the exact same commute everyday helps too. You know when to give some gas, when to coast, what light you're going to make and which one to just coast to, because you know it's going to be red.

And just one other tip: when you get to about 30-35 miles per hour, start lightning up on the gas until the iFCD is 50mpg or more. Try to keep it there as you slowly accelerate. Once you approach the speed limit (or less) get that iFCD closer to 100mpg. The longer you can keep it close to or at 100mpg while your driving the better your results.

Just practice, practice, practice.

 

All the rest of you advice is very good. Getting too dedicated might make you a menace on the road and might be a safety issue as well. So long as other traffic has an easy way around you it is probably OK to play, let em go around. Impeding traffic is rude and illegal.


http://definitions.uslegal.com/i/impeding-traffic/

 

Uh oh, here we go again...

Big Tuna, even driving the speed limit can get you negative reactions...

 

Again? Have we done this before?

Yes I understand that, however that isn't exactly what you said here:
Do you think it is a good idea to give advice that might get someone a ticket?

Even if you don't get a ticket you are likely to get pulled over and tested for DWI/DUI if you are driving noticeably slow. Care to guess how I know that?