[Eugene Bilich]

I own a 2001 Insight 5S. It has 33,000 miles. I live in Wisconsin, in the country, so most driving is county highways, 5 to 20 mile trips.
Historically in summer I get 65 to 70 mpg. In wintwer 55 to 60 in 0 to 25F weather.
This July after my 30K "routine maintenance" my mileage dropped by 5MPG the very next tank. Also the check engine light came on. The latter required a new O2 sensor. After bringing it in for recheck, the mechanic said there was nothing wrong with the car, so I've been stuck with this lowered mpg ever since.
I called the national help line and got the same BS.
Who elese has had a similar problem?

 

[Tim Maddux]

Did the dealer lower your tire pressure?

 

[cakley]

Did they use the correct oil?
Did they overfill the oil level?

Are you sure :?:

 

[activehope]

decreased mpg

Eugene,

I have a very similar drop in mpg, 58-59 avg. during spring & summer, now down to 49-52 when doing mostly city driving. I have a 2000 Insight, which I just bought in April.

I wonder if my mileage drop has to do with the batteries. When I did a 50 mile highway trip 3 days ago, my batteries were well charged and I got great mileage (58). Ever since, my battery meter has stayed at 3 bars and I've been getting lousy mileage.

I'd like to know your thoughts.

 

[gyeager]

MCU?

Eugene:

Did you have your MCU changed when you were serviced? I have my recall notice, but am afraid to let the dealer touch the car. It's working too well.

My lifetime is 66.0. Winter is about 60 and summer is about 72.

 

[Rick]

gyeager, I've been told that if you have them order you a new ecu for the recall you get the 04 flash now. A friend of mine's parents have a 01 and they said they got a letter in the mail saying they still hadn't done the recall and that they risked voiding warranties if they didn't so they had it done. The shop manager told them that they had a new flash. Afterwards their car seems to be getting better mileage, but I understand your concerns with letting them touch the car.

 

[cakley]

is there another ECU recall?
I did a ECU recall over a year ago.

 

[Rick]

No, but if you've put it off this long I've been told that they are using the 04 flash now. As long as you had it done your ok. Don't quote me on that, thats just what I was told. They said the car is getting a little bit better mileage too compared to before having the new ecu installed.

 

[counselorkv]

I haven't had my ecu replaced yet, for fear of lower mileage. If I went to have it done do I ask if they are using an "04 flash"?

 

[Rick]

Well, thats just what I was told. If you go and ask about it they might not have a clue what your talking about. Since your just a few hours away I might recommend taking it to the Honda service place in Mesa, they are a Honda service center with no dealership attached to it! It's the only one of it's kind in the southwest that I know of. They do good work. This is the place where my friends parents took their car for the replacment. I've never heard of anyone having a bad experience with them.

 

[Motty82]

Can someone explain what this "Flash" thing being discussed is? Is it sort of like a computer memory device?




Thanks for the definition Tim! : )

 

[Tim Maddux]

A "flash" is an erasure and rewrite of a reprogrammable piece of memory, like EEPROM or "flash memory." The ECU (as others have noted) has one of these types of memory from which it gets parameters for controlling the engine. This allows the Insight (or other cars with similar reprogrammability in their ECU) to be tuned.

EDIT - I'm not sure but I think the term "flash" could date back to old EPROM which could only be erased with a burst of UV light - a literal flash.

 

[Susan Haines]

Same thing happened to me

My situation is very similar on my 2000 Insight. I always had MPG in the high 50's or 60's depending on time of year. A couple of months ago I was driving and the "Check Engine" light came on and my mileage immediately dropped to mid 40's. The dealer replaced a "bad oxygenator" and my mileage has stayed in the 40's ever since. The tech is saying that is not abnormal, but to me it is because I know my car's history! I have taken my car in for every recall of parts and have always had my scheduled services. Feeling very frustrated.

 

[Willie Williford]

So what is an "oxygenator", Can't find one on my Insight and it's not listed in the "bible". (data base) I think what the mech. is trying to say is 02 sensor. If not................... then I would find another mechanic.

If your number 1 O2 sensor is going bad, you will definately see a drop in your mileage. If they have replaced the before mentioned sensor, how many miles have you driven since then?

My suggestion: Post the area where you live and maybe some INSIGHTER will meet with you and do a comparasion evaluation, and you will be able to obtain a valid "second opinion".

 

[Susan Haines]

No, it is the O2 sensor; my bad. I have driven over 1000 miles since it was replaced, with mileage of 48 mpg over that time. The lifetime of the car had been almost 60. I live in the Ann Arbor, MI area.