V8 idle fuel efficiency??

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What's it cost to run A/C with or without radio per hour just waiting around?

I know in econobox it's cheap, like 1/4 gallon per hour even in Nevada desert heat.... but what about our V8's??
 

08T1

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Nothing about our vehicles is great at idle.

Interesting question.

So much heat soaking happens at idle. Not to mention in a very hot location.

In SV , AZ mine will idle up to 1K rpm on idle to help with AC and emissions.

It's not a diesel. It's really not a great vehicle to run long at idle.

But I'm interested in hearing others opinions.

CJ
 

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Get an UltraGauge or Bluetooth OBDII gauge and see what it burns at idle.
 

John Christopher

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What's it cost to run A/C with or without radio per hour just waiting around?

I know in econobox it's cheap, like 1/4 gallon per hour even in Nevada desert heat.... but what about our V8's??

I don't know the gas usage at idle for the air but I the radio being on or off would make little to no difference.
 

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V8 idle fuel efficiency

I would say that the fuel efficiency at idle is a dumb question You are getting 0 MPG's at idle Not very efficient But then again I guess it is important to some people to know just how much gas they are wasting by sitting and letting the vehicle idle

Plus to many variables to get a true answer Idle RPM's Fuel Pressure etc.

But if its a matter of life or death to know the answer then I would suggest that you invest in a precision flow meter to get a accurate reading

Or if its also that important to know the answer then just don't sit and idle and waste fuel
 
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Gallons (or fraction thereof) PER HOUR


Duh.

Ever had to wait for something or somebody in a sunny desert city with a nice big ozone hole, in the summer? For an hour or two, not 5 minutes??

*IF* you can find parking angled in the right direction, sitting in the trunk with the liftgate up for shade & air can be okay-ish.... but waiting outside in the sun, not really an option. And all windows down tends to put you right back at the mercy of the sun...and, besides, our trucks' window area to interior volume ratio is pretty tiny, so it'll still get real hot, real fast

V8 idle fuel efficiency

I would say that the fuel efficiency at idle is a dumb question You are getting 0 MPG's at idle Not very efficient But then again I guess it is important to some people to know just how much gas they are wasting by sitting and letting the vehicle idle

Plus to many variables to get a true answer Idle RPM's Fuel Pressure etc.

But if its a matter of life or death to know the answer then I would suggest that you invest in a precision flow meter to get a accurate reading

Or if its also that important to know the answer then just don't sit and idle and waste fuel
 
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It's not a diesel. It's really not a great vehicle to run long at idle.


Actually, modern turbo diesels are AWFUL at idling... all that alphabet soup DPF EGR DEF SCR nonsense gets royally messed up by lengthy operation at low RPM, and then you need to run it real hard for a while to blow all (well, more like some of the) crud out again

Besides, Ford has made tons and tons of V8-equipped fleet PPV and SSV vehicles (mostly Crown Vics, but F150s and Expeditions too), which were made specifically with clients who needed a lot of idling hours in mind...
 
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f150dave2002

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I have a scan gauge 2 on my 2007 Expy. I was curious about this too. I have found it runs about 7 tenths of a gallon an hour at idle. I do not remember how hot it was or what accessories were running but that's my experience with the 5.4 V-8. I'll try to steal the Expy back from wife and see what it says and report back, otherwise the scan tools are a nice gizmo to have as well.
 
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I have a scan gauge 2 on my 2007 Expy. I was curious about this too. I have found it runs about 7 tenths of a gallon an hour at idle.

Ugh....AC, $2 / hour.


Then again, that's not that bad, not in midsummer in the desert.
 

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better get a second job so you can afford the cost

But then again now you know what his expy uses but you still have no idea what yours uses You wont know unless you check your expy could be more or less.
 
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better get a second job so you can afford the cost

But then again now you know what his expy uses but you still have no idea what yours uses You wont know unless you check your expy could be more or less.

Maybe it IS due to work that I sometimes need to wait around and kill time somewhere in the truck for a couple of hours??

And maybe YOU ought to get a part-time job or at least a hobby so you're not so bored in your retirement that you find yourself compulsively trolling online strangers young enough to be your grandkids???


Really.... one'd think you might know better by now...
 

Bedrck47

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Does it bother you that I see through your BS Is it really that important that you had to ask someone to figure out how many gals per hour you waste sitting at Idle Or you just to lazy to figure it out yourself. Invest in a flow meter then you would know what your expy uses Not what someone else's expy uses
 

f150dave2002

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dash photo 1.JPG A scan Gauge 2 is really useful... I recommend one for bored car owners of many types of vehicles... I did not get a chance to steal a look at my wife's Expy but here is a photo from 20k miles ago...
 
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Does it bother you that I see through your BS Is it really that important that you had to ask someone to figure out how many gals per hour you waste sitting at Idle Or you just to lazy to figure it out yourself. Invest in a flow meter then you would know what your expy uses Not what someone else's expy uses

Cuz the correct solution to a basic question that someone could surely answer (and did!) is OF COURSE to go buy **** I won't ever use again....

Like, duh.

Truly, with age comes wisdom.
 

jeff kushner

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A "typical" auto engine burns approx 1 gal per hour at idle....this would include any 4 cylinder through a V8. Note the "approx"....the 4cyl might be .85 gal while a 6L V8 might be 1.1 but both will be close.

It's a rule of thumb in the "Engine world" for the past 20 years and is still pretty accurate.............you might save 15 or 20 cents if you shut off the AC though since the compressor interlocks to raise the idle up to compensate for the load.

jeff
 

f150dave2002

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28f5dd1c5c5c479f02991f386e9f3e37.jpg


Ah, this is where that thread went. So I was able to get into wife's Expy and take an updated picture. The GPH or gallons per hour is in the lower right of the scan gauge display. It was 72f outside according to the Expy climate display. So just under the 7 tenths of a gallon an hour. It's kinda nice to know the ball park figures in case you are stranded or stuck somewhere.


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