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[omega3.0mv6]

hi i was wondering ive noticed my computer on idle is reading 0.5 mpg is this correct? my last omega only said 0.3 with same engine size

thanks

[sport]

Hi it should read 0.2 with aircon and electrics turned off

[omega3.0mv6]

ok so im assuming i may have a small problem cos its reading 0.5?

[PhilRich]

ok so im assuming i may have a small problem cos its reading 0.5?

Not so small mate! your motor is drinking fuel more than twice as fast as it should at idle!

[sport]

just tried mine withe air con on it read .4 pressed the off button it went back to .2 after about 10 seconds is your air con and fans turned off

[omega3.0mv6]

my aircon is disconnected at the moment cos the rad is nackered so i disconnected the pump but for some reason on cold start up it idles really bad very hesitating abit misfire but when warm seems to get just abit better but engine still jogging more than it should and i think it is running abit rich im getting 350 miles on a full tank abit of town driving but mainly  motorway driving ?

[SPEED HARRIS]

Mine reads 0.3 at idle, so it is running rich? How can I correct this? (I know bugger all about cars) 

[Rockhampton]

Mine shows .5-.8 at cold start, but once to temperature, it is .2 with A/C and lights off, .3 with one or both of them on 

[feeutfo]

my aircon is disconnected at the moment cos the rad is nackered so i disconnected the pump but for some reason on cold start up it idles really bad very hesitating abit misfire but when warm seems to get just abit better but engine still jogging more than it should and i think it is running abit rich im getting 350 miles on a full tank abit of town driving but mainly  motorway driving ?

Check for fault codes via paperclip test in maintenance section, if no codes suspect misfire, possibly due to oil in plug wells due to blocked breathers.

But do paper clip test and report back the results 

[pembsomega]

surely the higher the reading the better? its miles per gallon not gallons per mile??

when you running on the move you want the highest number possible, why would it be different standing?

[Entwood]

At very low readings it's actually gallons per HOUR on mine ..

so the lower the better ..  mine is 0.3 aircon off 0.4 aircon on ...

How can it be anything to do with miles when you are STATIONARY !!!!

[davethediver]

surely the higher the reading the better? its miles per gallon not gallons per mile??

when you running on the move you want the highest number possible, why would it be different standing?

On the move yes you want a higher number in MPG but at idle when so little fuel should be getting used the trip computer measures in Gallons oer hour hence 0.3 which i think is pretty much standard is a better reading than 0.5 gallons per hour

EDIT Must type quicker 

[pembsomega]

At very low readings it's actually gallons per HOUR on mine ..

so the lower the better ..  mine is 0.3 aircon off 0.4 aircon on ...

How can it be anything to do with miles when you are STATIONARY !!!!

thats what was confusing me i was reading the thread thinking surely it should be 0.0?? then why did everyone want a lower number??

gallons per hour at stationary makes much more sence

[Kevin Wood]

The lambda loops will ensure that the engine is always running with the correct mixture (assuming it has gone closed-loop). They do this by adjusting the injector duration until the composition of the exhaust gas is correct.

The MID estimates fuel consumption based on the injector duration the engine ECU is using and the assumed flow rate of the fuel injectors. They don't measure fuel flow rate so can't really be relied upon. Injector duration might be longer than "normal" due to a decrease in fuel pressure or quality, injector flow, or because there's a slight increase in airflow into the engine.

I wouldn't regard a variation in this reading as suspicious unless there are running problems or codes being thrown by the engine ECU.

Kevin

[TheBoy]

on a 3.0l, the most usual figures (once warmed up) are:

idle, no a/c - 0.3gph
idle, a/c - 0.4gph
idle, a/c, in D (auto) - 0.5gph

2.5 and 2.2 often 0.1 less...