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Hi All:

___From my understanding, a 5 speeds Lean Burn can give a boost of ~ 20 mpg on the Instantaneous bar graph when it is evoked (if it can be evoked?). My real question is can a novice Insighter get into Lean Burn on a test drive with a passenger (salesperson or private party) at ~ 60 - 65 mph on a relatively flat highway? Would it be sustainable for minutes/hours or do you constantly fall into and out of lean burn while traversing flat ground? Is 60 to 65 mph to fast for Lean Burn as I have not seen any discussion of the speed range in which lean burn is possible on any particular Insight? When you arrive at Lean Burn, does the Instantaneous jump to 60, 80, 100 mpg or does something else happen? I may as well ask, is Lean Burn available at almost all speeds up to and exceeding the speed limit or just when you travel under 60 mph?

___I would like to use this as a test as a quasi diagnostic in case I were to make an offer on a particular Insight? If Lean Burn mode is available at 60 – 65 mph w/ 2 passengers (I weigh 200 myself and I assume a passenger would weigh 125 to 200 as well) the engine is more than likely in tune I would assume? Is this assumption valid or are there other considerations when buying a used Insight in regards to the engine tune and capabilities?

___Lastly, is there a light or indicator that lights up on the FCD when Lean Burn is reached?

___One other quick question that has nothing to do with Lean Burn … Does the Insight have an outside air temperature display? I have one in the Corolla and the MDX and I love it!

___Thanks in advance once again …

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:3di81t27][email protected][/email:3di81t27]
 

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can a novice Insighter get into Lean Burn on a test drive with a passenger (salesperson or private party) at ~ 60 - 65 mph on a relatively flat highway?
Yes you can, but since you are a beginner you might have more luck trying at 50 or 55 mph just in case there is a head wind and the tires are 32psi instead of 40+ psi.
The extra weight doesn't matter when you are travelling at a constant speed on level ground. Try the following procedure to get into lean burn easily:
- On level ground drive at 50 mph in 5th gear
- now accelerate very slowly until 55 mph and then hold that speed constant for 5 seconds and watch the instantanous MPG guage.
- now ease off the throttle very very slowly just a small tiny amount until you see the instantaneous MPG graph quickly show an improvement of about 20 MPG, now hold the throttle there.
-You should be travelling at the same speed or maybe 1 or 2 mph slower but getting much better fuel efficiency, you are now in lean burn.
If you lost some speed, very gently and very slowly press the throttle to SLOWLY accelerate to 55 mph again.

Would it be sustainable for minutes/hours or do you constantly fall into and out of lean burn while traversing flat ground?
Lean burn can only be maintained for a few minutes at time but if you don't move your foot at all, it will come back after a few seconds of running rich.


Is 60 to 65 mph to fast for Lean Burn?
Learn burn can be maintained at those speeds but it depends on the wind, tire pressures and road surface. Lean burn only happens when the engine is at a low effort, it's not speed dependent so you can go into lean burn at a very high speed if a strong wind is at your back and/or you are going down hill.

There are no special lights to tell you are you are in lean burn.
You will only know you are lean burn because the instantaneous mpg graph very quickly improves when you ease off the throttle a little while you are maintaining your speed.


Does the Insight have an outside air temperature display?
No, but I've seen that they are available aftermarket for any car.
 
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Hi Guillermo:

___Thank you for answering all of the questions posted above. With your experience, I should have a much better insight (no pun intended ;)) in regards to a particular Insight on my first test drive coming up later on this week.

___Thank you once again.

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:10slkw4u][email protected][/email:10slkw4u]
 

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"Lean burn can only be maintained for a few minutes at time but if you don't move your foot at all, it will come back after a few seconds of running rich."

What you see there is something called a "NOx purge". As I understand it, lean burn actually creates quite a bit of nitrogen oxides (bad for emissions). The Insight's catalytic converter actually collects these, and when the computer decides that the collector is full, momentarily enrichens the mixture to burn them off.
 
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Hi James:

___Thank you for the detailed explanation. With the Insight at 55 mph and steady on a relatively flat section of hwy (we have a lot of that here in North Eastern IL. and South Eastern WI ;)), I should see “Lean Burn” for ~ 5 minutes (I am guessing?) with the instantaneous sitting around the 70 - 80 mpg mark. After ~ 5 minutes, The “NOx purge” cycle should/will happen and your mileage will drop to the low 50’s/high 40’s. After ~ 10 seconds of “NOx purge”, the Insight’s instantaneous readout should jump right back up to ~ the 70 – 80 mpg mark again? Does a 5 minutes on (~ 70 - 80 mpg), 10 seconds off (~ 50 mpg), 5 minutes on (~ 70 - 80 mpg) schedule sound about right for an Insight’s “Lean Burn” capability on a test drive? I just want to make sure as it sounds like a great way to find out if the EGR, a catalytic converter, the O2 sensors, or anything else is possibly wrong with a particular Insight’s engine without having to connect up an OBDII Scan Tool or similar high tech wizardry before I would make the purchase decision ...

___Thanks in advance once again.

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:3j5idil1][email protected][/email:3j5idil1]
 

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Since you don't have experience don't get disapointed if things don't go like clockwork, like you described.
 

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I see more like 2 minutes between lean burn cycles. You can actually feel them if you're paying close attention: there's a little bit of a surge, as though you'd stepped on the gas.

I see it more around 65-75 (since I don't do much 55 mph driving, except up hills). Given a slight downgrade, such as on the down side of a freeway overpass, I'll see the mpg go to around 90-110, vs around 75 "normal", or 50 in purge.
 
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