high mileage efficiency

[Matt1]

I am wondering how fuel-efficiency holds up on Insight's with high mileage. What kind of mpg losses have owners experienced? What factors cause this mpg loss - internal combustion engine wear, fuel system components, 144V battery? I want to buy a Civic Hybrid 2003-2005, and wonder if there is a significant mpg loss on high-mileage vehicles which may make it's mpg not much better than a non-hybrid vehicle. I think this forum is the best place for me to pose this question.
Thanks.

[Jivko57]

I would like to know the answer on that question too..

In my opinion every imperfection with the car affects mileage, luckily after 14 months with my insight I think High mileage on the insight 1 engine does not affect the efficiency so much, for example between the weather improvement and grid charging each night i am averaging close to 72 mpg on this tank, only a year and 30k miles ago my average in Feb 2010 was 62 mpg..

So the engine wear probably decreases overall performance, but there are numerous other things (to start with the ones I know about): clogged EGR plate, bad EGR, clogged injectors, bad ignition coils or spark plugs, bad 12v and/or IMA battery, missing under body panels, A/C usage, cold weather, snow, rain, low pressure in tires , incorrect oils..... all of these may have a dramatic effect on the mpg and you can get them in a relatively low mileage car too..
Also the car is so sensitive that in a flat roads and warm weather state would get much better mileage than in a cold and hilly state...

May be the best way of checking the overall condition of the car and MPG in relation of others of the same kind is to go to a hybrid-fest or similar event where there are many cars of the same model driving in the same conditions and route and at similar speeds . such a test probably would not be 100% indicative to the car condition, as each driver has different style and hypermiling skills, but at list will eliminate some of the other variables...

[Matt1]

Jivko57,
It is encouraging to hear that high-mileage on the internal combustion engine has not substantially affected your mpg. You may still have good compression.
I read 1 post that said that wear in the gas engine on high mileage vehicles lowers mpg. Could lower compression on a worn engine impact mpg, and also maybe make it more difficult for the engine to engage lean-burn.
All of the items you mention as affecting mpg are not that difficult to deal with and should be part of the maintenance of the vehicle. The exception is the traction battery, but a company named Re-Involt has a Li battery replacement for the Insight and Civic Hybrid coming available in March.

[Jivko57]

That is great news, but the benefits over the nimh battery may not justify a big price difference..

The battery in the insight is mostly needed for hard accelerations and to start the engine , also it is a great place where to save energy recouped from regen from braking and slowing down ....

On mostly highway driving , like mine (90-95%) I guess , It does not make much difference in MPG.

On the other hand regarding keeping the car in good shape I think , the dealers are not helping too much there as the car I bought was dealer maintained ( same dealer for 10 years)

It was in bad shape when i bought it and still has many things to be done to be brought into the mechanical condition it should be in.

One small thing to illustrate why I think some of the dealers are doing a bad job on the insights is the fact that after the oil was changed with the same dealer for 10 years the oil drain plug had stripped thread, they just put a bigger plug there and screwed it on. Oil was leaking and the car was low on oil when I bought it.

So much for the tale that a dealer will keep your car in a good shape.

So the owners with mechanical skills are better off doing the jobs themselves and for those that lack the skills finding a reliable auto repair shop and trying to be on top of things is the only option....


So I am studying what the others here are doing in the upkeep of their insights and trying to get to know the car and what is happening under the hood before it is too late.

[Matt1]

The Re-Involt Li battery should be the same price as the NiMH, and it is supposed to solve the reliability problems with the 144V battery. Also, it may increase mpg - Honda is switching to Li in the new Civic which shows an increase of 4 mpg over the older Civic model.
Hopefully, other Insight owners will give information on how their mpg have held up on their high-mileage vehicles.

[MN Driver]

480984 miles 54.0LMPG
Not bad in my opinion, hard to tell what the driving style was because if I drove my car like any other car and didn't try to grip lean-burn tightly or coast to stops to the same extent as I do now, that would be roughly my current mileage on my car with less than 1/4 of that mileage.

Post 22 of this thread
Also check out post 19 as well, amazing reliability statement. Tires, cracked oil pan, battery, and trans bearings(probably mostly the ISB but could have been a full rebuild), that's it according to the owner.
Highest mileage of an Insight?

[Eli]

I'm sure the original poster of this thread is long gone, but I stumbled upon it and thought I would cross post a bit.

The Insight at 444,000 Miles: First Roadtrip