Mitsubishi: fuel consumption enigma

In article <googlegroups.com>,
be says... 

<rest snipped>

Causes of poor fuel consumption include (in no particular order):

1) Failed / failing lambda sensor (also known as oxygen sensor). See
http://www.picotech.com/auto/lambda_sensor.html

2) Incorrect tyre pressures

3) Failed thermostat - does the engine get up to operating temperature
OK?

4) Failed temperature sensor - if it gets to the right temperature, does
the engine managament system know it?

5) Binding brakes - do any of the wheels feel far hotter than they
should? Does the car "Lurch" to a halt, or gently glide to a stop?

6) Fuel leak - should be obvious by the smell! (But I guess if the
computer is showing poor economy this is not the case for you..)

and finally, and most obviously

7) Forgetting to remove roof-rack, trailer or caravan ;-)

Ian
--
Ian Riches
Bedford, UK

"Ian Riches" wrote
 

In this case it's not poor fuel consumption,
it's an exceptional good fuel consumption.
 

If a fill up at the gas station confirms the onboard computer,
it's probably not faulty.

Don't touch the perfectly running system!

Thomas

Ian Riches (com) gurgled happily, sounding much like they
were saying :
 
 

Umm, Ian...

6.2l/100km is 45mpg
5l/100km is 55mpg
4l/100km is 70mpg.
 

So this is the economy that the trip computer's reporting? Personally, I
think the computer's lying through it's teeth...

(I presume it isn't *really* doing 70mpg? If it is, find the problem, and
bottle it. You'll make your fortune.)

In article <d8m8k7$hhh$she.de>, de
says... 

Ooops. Teach me not to read properly and confuse my l/100km with mpg.

In that case, look for air leaks.....

Ian
--
Ian Riches
Bedford, UK

In article <153.244.170>,
com says... 

I know. Blame confusion of l/100km and mpg, not being used to people
complaining about *improved* fuel economy and publically embarassing
lack of comprehension skills.

I suspect one of those may be more to blame than the others.

Oops.

Ian
--
Ian Riches
Bedford, UK

Ian Riches (com) gurgled happily, sounding much like
they were saying :
 

<snort>

A definite rarity...

"carl" <be> wrote in message
news:googlegroups.com... 

Pop your spark plugs out and have a look at them to see if there are signs of it
running lean.

The fuel consumption is normally calculated with the injection time on
this injector by the ECU. The fuel consumption is given as frequence
signal to the computer. This is most of the system anyway.

A really good fuel consumption can mean a lot of thing, from the ecu
calculating wrong to a computer problem. As your engine is still
running fine, I do not thing that the ECU is gone.

I will personnaly tip on a signal problem betwwen the ECU and the
computer. This could be chekced by any good repair shop.

Another possible problem is the mileage of the injectors. In some
cases, large mileage injector tends to inject far much more than
normal. Therefore the ECU will correct the injection volume by dropping
the injection time, reducing the calculated fuel consumption. However,
you will see it on your gas exhaust measurement, normaly the Nox, COx
and HC are exploding !

Well I will recommend you to have your electric system checked !

Regards

Jerome Douay
www.Team74.com