Honda Insight Forum banner

1 - 10 of 10 Posts

·
Super Moderator
Joined
·
4,690 Posts
Discussion Starter #1
I just bought a 2003 CVT for my wife and I'm about to take it on a 2,500 mile trip. I have changed oil and CVT fluid, and I aired the tires to 45 lbs. The IMA seems strong, and is very active. I know I will greatly miss lean burn, MIMA, and FAS. And the turbo. I expect to drive 65-70, but we'll see. I won't have the incentive to slow down to stay in LB.

Around town we've been getting high 40s and low 50s. Will it be better on the highway?

What else can I do? When do I use the S button? What is the MPG hit in S? I haven't seen the need for it around town. Hills and long grades?

Thanks for any suggestions.

Sam
 

·
Registered
Joined
·
1,814 Posts
Your mileage seems low for the city driving, but you did not explain what your city driving actually involves. Sport mode will impact your mileage. I only use it when needed, such as a freeway on ramp. Once on the freeway I will go into sport mode if I am going up a hill and the assist kicks in.

Sport mode allows more assist, maybe a little sooner, and kicks up the revs a bit. Even driving on level ground the revs are higher when in sport mode.
 

·
Hypermiler
Joined
·
3,650 Posts
I don't use S mode except for rare occasion on the mtn. My in town driving nets in the 50's, using slow / gradual pull outs and accel's. I hypermile it hard, slowest guy on the interstate, but my area is ideal for h/m 'ing. lmpg 66 + on 21k miles.

Since buying the mt last summer, I have found I have to drive each car differently. The mt a little more aggressive to reach cruising speed and then lb, the cvt much gentler and slower.

Full rad block (adjustable), lower grill block, and adjustable warm air on the cvt helps somewhat. Tires aired up pretty high, brings some 'spirited' discussion.

Rough guess on the long trip at those speeds, low 50's for mpg.

edit: hm 'ing to work with good conditions : 60's,. Going home (mostly downhill) 80's, broke 90 a couple times, but that was only when the planets aligned.
 

·
Premium Member
Joined
·
331 Posts
The absolute best I've had at 70mph was 52-53mpg if I really work hard at it between 65-70mph usually I get 50 right in the nose but usually high 48s low 49s. If I just drive 70 with no extra effort about 46.5 to 47.

Around town so many variables but just driving reasonable not hypermiling prolly 42 to 44mpg

The best short little 60 mile high run at 35-50mph 68mpg

Same run in my mt 92mpg for comparison.

Curious to see once I get my cvt lean burning if I can beat the mt.
 

·
Hypermiler
Joined
·
3,650 Posts
Thinking on the fly here. Apologies for the length.

Hilly terrain around here seems to suit the Red nicely. I take advantage of the downhill grades, they don't have to be steep.

I read about trying the metric display of the fcd and gave it many tries. Took some getting used to. "There's mpg beyond the 150 mark".

150 on the display works out to a little over 1.5 L / 100 km (or about 3 of those little squares above the 0 mark- I call them spots.)

Easing up on the fuel to a '2 spot' or a '1 spot' nets about 230 mpg or 460 mpg. Quite touchy on the throttle. Folks accustomed to lb should have no trouble.

On the obd, observing parameter #83 on the ecm (fuel injector duration , 'fin') is helpful. Get the fin down to about .5 or .6 and you're in the 2 spot area. Around .35 to .45 is a 1 spot. Nice visual aid to help with easing up on the foot.

But ... speed can affect ability to do this. I found at 90km/hr speed (a little over 55 mph) I can't get a 1 spot without the car surging in and out of regen, so I keep the speed down when starting onto a decent. If it's a steep decent, I go into the obd and tell the soc it's 80%, eliminating regen and allowing fuel shut-off for what bit of coasting a cvt can do (air pumping still a factor).

That's probably as clear as mud.
 

·
Premium Member
Joined
·
331 Posts
If it's a steep decent, I go into the obd and tell the soc it's 80%, eliminating regen and allowing fuel shut-off for what bit of coasting a cvt can do (air pumping still a factor).

That's probably as clear as mud.
I know exactly what you mean.

For my driving style/skills I find my best mpg in the cvt while battery is full as your doing and coasting. For me though if I first start the car off with full battery I get much greater coasting distances (because no cut fuel mode with freshly started engine) as the car just seems to glide almost perpetually. Unfortunately once the engine warms and I try this same tactic while the regen doesn't scrub speed or momentum (bc the battery is full) the fuel cut mode sure kills momentum and thus mpg.

That very scenario for me is why I can always trump the cvts mpg with my mt. My mt easily allows full fuel cut (FAS) while having zero pumping loss as I'm free coasting in neutral.

This can be somewhat attained painstakingly in the cvt by shifting to neutral and then key off the car and coast until restart is needed and then shifting back into drive. This practice has been preached as a big NONO in the cvt world because of increased cvt wear from shifting in and out of neutral repeatedly while still coasting especially at highway speeds.

I generally use my IMAC&C and push up/down once to override stock ima behavior and this allows regen-less coasting then I try to meticulously lift my accelerator ever so slowly and watch my TPS reading on the odbiic&c until I reach 10 and then finding the "sweet spot" or lowest possible throttle without ecu calling for fuel cut. I estimate this would be around 9.65 if the TPS readout had finer resolution. Anything lower than the 9.65 TPS and the car lurches and drags a miserably short coasting distance thanks via significant cvt drivetrain losses + wasted unneeded engine pumping losses both killing mpg while adding unnecessary wear to cvt and engine.

Im not sure of a way to eliminate the drivetrain losses without some additional wear of releasing and reengaging the start clutch.

Maybe someone more familiar with the cvt workings. Jeff rebuilds them he might have some ideas. Peter has spoken of tinkering with the tcm to adjust ratio on demand this might hold the key to better mpg.

On the engine pumping losses maybe some kind of ecu trickery to prevent fuel cut by simulating cold start repleatedly or whenever a coast is desired by the push of a button would help mpg.
 

·
Hypermiler
Joined
·
3,650 Posts
Tried neutral, and neutral with key off (on the cvt). Engine raced when I put it back in Drive. Didn't do that anymore. On my trip home, the mountain decent is steep enough to go fuel shut-off and still accelerate. That's how I routinely get 80's (in good weather) and 90 + when the planets align (all green lights in the home town).

Agreed on the mt, I can fas and coast far greater distance than the cvt, netting 110 with ease on the trip home. (80 + on the trip up to work)

Back to Sam's question, I find the cvt does 15 to 20 less mpg on the 50 legs to / from work and the 100 mile round trip. I see the same for highway speed travel when hurrying across state.
 

·
Premium Member
Joined
·
421 Posts
Congratulations on picking up another Insight!
 

·
Super Moderator
Joined
·
4,690 Posts
Discussion Starter #9
Thanks for the tips, everyone! The first tank was 63.9. I'm pleased. We did have a tailwind for part of it and we dropped about 4,000 ft in elevation. To offset this I was driving faster than I normally do. The car did fine, but I really missed the green light on the OBD gauge. It also took me about 50 miles to stop reaching for the joystick. It's a good car.

I was amazed at how quickly and completely I had gotten used to Scott's springs on my other car. This car hit bottom all the time. Very annoying! I'll order a set of springs for it as soon as I get home.

Sam
 

·
Registered
Joined
·
250 Posts
Thanks for the tips, everyone! The first tank was 63.9. I'm pleased. We did have a tailwind for part of it and we dropped about 4,000 ft in elevation. To offset this I was driving faster than I normally do. The car did fine, but I really missed the green light on the OBD gauge. It also took me about 50 miles to stop reaching for the joystick. It's a good car.

I was amazed at how quickly and completely I had gotten used to Scott's springs on my other car. This car hit bottom all the time. Very annoying! I'll order a set of springs for it as soon as I get home.

Sam
That's great mileage Sam, have a great time and tell Carol we said hello.

George & Kym
 
1 - 10 of 10 Posts
About this Discussion
9 Replies
6 Participants
desertracker
Honda Insight Forum
We’re the ultimate Honda Insight forum to talk about Honda’s hybrid car and its fuel economy and specs!
Full Forum Listing
Top