Honda Insight Forum banner

1 - 20 of 36 Posts

·
Super Moderator
Joined
·
7,158 Posts
Discussion Starter #1
I'm currently in souther LA and am seeing some things which appear to be improvements. First, Bright sunlight on the roads seems to warm the road surface better, and allow the tires to run warmer. This looks like a genuine improvement of a few MPG.

Just put in a tank of mid grade fuel, and that also appears to allow the timing to run a bit more advanced, particularly with 115 IAT. Looks like a few MPG.
 

·
Premium Member
Joined
·
9,861 Posts
jime:

Southern LA or Los Angeles?

Willie
 

·
Super Moderator
Joined
·
7,158 Posts
Discussion Starter #3
jime:

Southern LA or Los Angeles?

Willie
Louisiana for Mardi Gras:D

Having real warm weather here so I'm polishing up some of my technique and trying to learn more about the car. After all this time, I'm still learning, but the car so hard to calibrate that one doesn't really learn what one thinks he is learning;) I definitely think a warmer road surface is a big help.
 

·
Registered
Joined
·
443 Posts
I've popped in a few tanks of midgrade along the way. My calculated average with it is 1.1 MPG lower than with regular. I've got 58 fill ups w reg and 24 w mid. I wonder if there is a different BLEND being used down there. I know with diesel they switch between a winter blend and "regular." Maybe you are getting that good ol' warm region Bourbon St blend!

On a side note, our Dixieland band was down there this summer... Try to catch some of the really good sufft while you're down there! Maybe make it over to Preservation Hall. Get there early!
 

·
Super Moderator
Joined
·
7,158 Posts
Discussion Starter #5
Maybe you are getting that good ol' warm region Bourbon St blend!

On a side note, our Dixieland band was down there this summer... Try to catch some of the really good sufft while you're down there! Maybe make it over to Preservation Hall. Get there early!
I've been personally consuming the Bourbon St blend;)

Was shooting pictures of Preservation Hall at sunrise this morning. Love the looks of that place. No chance to get in this weekend with the Superbowl crowds in town.
 

·
Registered
Joined
·
894 Posts
I'm currently in souther LA and am seeing some things which appear to be improvements. First, Bright sunlight on the roads seems to warm the road surface better, and allow the tires to run warmer. This looks like a genuine improvement of a few MPG.

Just put in a tank of mid grade fuel, and that also appears to allow the timing to run a bit more advanced, particularly with 115 IAT. Looks like a few MPG.
I've personally noticed no advantages or benefits to running premium fuel in my red turd. Just my experience.
 

·
Registered
Joined
·
224 Posts
I know this is an ongoing debate on insightcentral.net. Some say it helps; some say it does nothing and may possibly hurt mileage. I was skeptical, but I may be changing my mind. Now, I think it is possible for some driving styles to see a solid improvement in FE.

I usually get low to mid 70s in the summer and low 60s in Ohio winters. In fact, I resorted this winter to doing much of my driving in fourth gear, as fifth couldn't maintain reasonable (i.e. 45-50 mph) speeds in lean burn. For argument's sake, I tried a tank of 93 octane from my regular Certified station near my house.

My results were surprising. I went from 62 mpg on my previous tank in similar weather to 66 on the nearly completed current tank. I know, I know, anecdotal evidence is not a scientific test, but I have a theory as to why it may work.

The best idea I could come up with as to why this may work is that the car may be able to hold the line at the edge of the lean burn envelope. I usually do a mild pulse and glide, where I will accelerate at the edge of lean burn up to the speed limit, then try to find a sweet spot that let's me decelerate the slowest. At about 45, I do it again. With the last tank, acceleration seemed to happen more quickly, and it took longer to decelerate to 45. I'm not saying it works for everyone, but I am going to test my theory further.
 

·
Premium Member
Joined
·
9,983 Posts
+!, gen 2 owners say the same. If you drive aggressively it performs better too. :D I was using 93 octane from sams club. It was also easier to modulate the throttle to hold the car in a range where it got better mpg regardless of speed.
 

·
Super Moderator
Joined
·
7,158 Posts
Discussion Starter #9 (Edited)
In fact, I resorted this winter to doing much of my driving in fourth gear, as fifth couldn't maintain reasonable (i.e. 45-50 mph) speeds in lean burn.
I have driven several cars which react in this way. And yes, my evidence is anecdotal also, but I have a theory of my own. I think it is possible that these cars have gasoline engines which are down on power for one reason or another. Maybe is it a leaking valve, or excess blowby, or some other problem. If the ICE is down on power, then the LB envelope is more narrow and the car will require more assist. I'd do a compression test on the ICE;)

At one time, I tried some dyno testing to try to determine if this was a factor, but Insight G1s do not react well to sustained WOT. They usually try to clear all the built up sulphur compounds in the catalytics and create a horrid stink in the garage. This may be a good thing for the car, but the garage owner lacks enthusiasm.
 

·
Registered
Joined
·
6,140 Posts
Some of us were discussing using premium fuel at another thread a bit ago. I tried a tank and monitored the knock sensor and timing advance from the OBDIIC&C. I went back to regular and I'm still on that tank, watching the Knk sensor. Just starting to feel pretty confident about observations that the Knk sensor is a lot more active with regular fuel versus premium; Knk sensor doesn't activate much under typical driving with premium fuel, mostly when you'd think it should activate, like under heavier loads. But with regular, even the air conditioning cycling when the car is idle will activate the knock sensor, retarding timing about 3.5 degrees; it's very active under normal driving conditions...

So, to the extent that advanced timing will improve fuel economy - that's the extent to which premium fuel will likely improve fuel economy as well... When I ran premium on that test tank a week or so ago, I did see higher mpg than I had in a long time, like maybe by 5-8mpg, can't remember exactly. But I had also installed an under engine aero panel, and the weather was just turning warmer, particularly on the day I was paying the most attention to fuel economy numbers... Anyway, pretty sure it makes a difference, but likely not to the degree that it makes financial sense to do premium all the time...
 

·
Super Moderator
Joined
·
7,158 Posts
Discussion Starter #11
Interesting eq1. Sounds like there was an improvement with the premium, but how much? Like all fine grain measurements, the Insight makes the job pretty tough;)
 

·
Registered
Joined
·
6,140 Posts
I'd guess at lest 2-3 mpg, but it depends on how much heavier-load driving one does. I mean, if you drove the full tank on regular, on the highway at a constant speed, where the knock sensor doesn't come on at all, then you'd see no gain. If you drove in-city a lot with starting and stopping and shifting, where knock sensor is most active, you'd probably see a good sized gain... I'll probably go back to premium next fill-up and watch some more knock numbers...
 

·
Premium Member
Joined
·
9,861 Posts
eq1:
How are you reading the "knock sensor".?
You can read the timing, but I guess that when you see the timing go "retarded" you "assume" that indication is when the knock senor is active.

Willie
 

·
Registered
Joined
·
6,140 Posts
The OBDIIC&C includes a parameter for the knock sensor - "Knk". This is the version 4 software; I don't think the one before that had Knk... I'm not watching overall ignition timing any longer, just Knk...
 

·
Registered
Joined
·
737 Posts
The OBDIIC&C includes a parameter for the knock sensor - "Knk". This is the version 4 software; I don't think the one before that had Knk... I'm not watching overall ignition timing any longer, just Knk...
No, V3 does not have KnK. I guess I need to dig up my pic programmer and update.
 

·
Registered
Joined
·
6,140 Posts
v4 has a lot of new parameters, actually. But one also needs the 18F pic; I think early builds had the 16F and maybe later ones came with the 18F....
 

·
Premium Member
Joined
·
9,861 Posts
What are the reading in Knk?
(curious)

Willie
 

·
Premium Member
Joined
·
9,861 Posts
OK, another favor:

Get going along in say 2gear at 2K and floor it...What is the Knk showing.
Then try 3200 rpm and floor it........What is the results?

Thanks
Willie
 

·
Registered
Joined
·
1,732 Posts
You mean the units? If so, it displays degrees of timing retardation; the most I've seen is -11 degrees...
Do you see the "-" symbol on the OBD2 display?

My V4 of the firmware also has numbers as high as 11 but doesn't display -11. I would expect the numbers to be shown as negative. I have a 2005 and Spk doesn't display any data other than "xxx". :(
 
1 - 20 of 36 Posts
Top