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HotRod10

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Message Posted: Mar 5, 2013 10:45:40 AM

I'd like to hear from people who have fuel monitoring devices, like a Scangauge, etc. about their actual fuel consumption at idle, both cold and warm.
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Madridjoe
Veteran Author Lancaster

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Message Posted: Mar 25, 2014 8:18:31 PM

I rarely let my truck idle, when I do I can watch the avg fuel mileage meter reading fall
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Houckster
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Message Posted: Mar 25, 2014 1:00:29 PM

I normally don't turn off the engine unless I know that the wait is going to be more than about 3 minutes. I normally plan trips to avoid busy intersections when possible.

When I restart my engine, it will run at about 1000 RPM for a couple of minutes, I don't know why but it reduces any benefits from shutting the engine down for any period less than 2-3 minutes.

[Edited by: Houckster at 3/25/2014 1:03:16 PM EST]
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dontuknowOH
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Message Posted: Mar 25, 2014 10:42:27 AM

When driving my econo, idling at red lights or for whatever reason is a concerned thought but not a mind bender. It happens so, engine run time will consume fuel, if driving the larger powered vehicle I can expect a very noticeable waste of fuel.

When pulling into a parking spot I often kill the engine before the vehicle stops moving(parked). Idling to me is like a dripping home faucet or a leaking flush valve on the john, then noticed when the water bill gets paid. Extra cost is extra cost that could benefit elsewhere in a person's leisure budget(Happy Stuff).

I have never installed any monitor to help me obtain a decent measure of idle costs. I have looked up the marine type of fuel flow gauge/read-out device, prices vary, and I imagine installation would be a bit more complicated for the average guy, messing with the automotive fuel rail to the injectors, where safety is a concern.

The econos don't bug me on fuel usage to a great extent idling hot or cold weather, I have improved to shorten that time interval as a benefit to my driving habits by DIY some ideas. That cost in items was minimal, also the labor time involved(retired). WFMe till I try again....
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contiki
Champion Author Ontario

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Message Posted: Mar 25, 2014 7:05:20 AM

I have no fuel monitoring devices on our Hondas........
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Vin63
Champion Author San Bernardino

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Message Posted: Mar 19, 2014 9:49:21 AM

Just a quick visual observation on the short diagnostic sessions for other things on the car, the average was between .35 and .40 GPH 2.0l TDI.
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Awing1
Champion Author Ontario

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Message Posted: Mar 19, 2014 8:53:42 AM

I don't have monitoring device, but It's good info from others. Thanks for posting this question.
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hoopitup2000
Champion Author Virginia

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Message Posted: Mar 19, 2014 7:51:01 AM

Cold ~.60-.70 GPH depending on how cold it is
Warm ~.16-.18 GPH

Corolla-1.8 liter-Manual trans-Scan Gauge II
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sagnat
Champion Author Riverside

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Message Posted: May 24, 2013 6:27:03 PM

Yep, good thing I have seat heaters :D

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HotRod10
Champion Author Wyoming

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Message Posted: May 24, 2013 9:45:45 AM

Excellent sagnat! Thanks for the info.

Brrr! All the way down to 60, huh? Boy, do I feel sorry for you ;)
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IAMCANADIAN73
Champion Author Ontario

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Message Posted: May 24, 2013 8:57:00 AM

I agree
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jack4141
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Message Posted: May 24, 2013 1:56:06 AM

I agree
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sagnat
Champion Author Riverside

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Message Posted: May 24, 2013 12:56:43 AM

OK hotrod, was able to check cold idle GPH this evening. Conditions, 60*F and car had been sitting for 12 hours. Cold idle showed .37 GPH compared to my warm idle of .30 GPH.

This on my 2.0 Litre Turbo Diesel.
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HotRod10
Champion Author Wyoming

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Message Posted: May 23, 2013 4:12:51 PM

"Experts say that a car idoling consumers more gas than people think !!"

The info I've gotten so far on this thread indicates that gas consumed at idle (particularly for a minute or 2 at a stoplight) is insignificant compared to other things that drivers can do to save gas. I'd never shut my car off at a stoplight, or any other time while I'm in traffic.

"I can't stand to see someone sitting in the car with the car running for nothing !!"

Why do you care? It's not your gas. Do you get as upset with people commuting in a truck that gets 8 mpg? Probably not.

[Edited by: HotRod10 at 5/23/2013 4:20:44 PM EST]
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pupule777
Champion Author New Hampshire

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Message Posted: May 23, 2013 11:08:26 AM

If we stop for any longer than an average red light I shut off the car. Experts say that a car idoling consumers more gas than people think !! I can't stand to see someone sitting in the car with the car running for nothing !!
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HotRod10
Champion Author Wyoming

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Message Posted: May 22, 2013 4:40:35 PM

"If you are going to set more than 5 minutes shut off the engine."

Thanks for the advice, not that it addresses that topic. By all means, shut it off and save a nickel. As long as you get rid of it before the starter goes out, you'll come out ahead.



[Edited by: HotRod10 at 5/22/2013 4:45:24 PM EST]
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HotRod10
Champion Author Wyoming

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Message Posted: May 22, 2013 4:08:08 PM

"newer cars will all have an auto start stop feature."

All? I doubt that, but I'm sure it's a gimmick that some will try to use. a few already do.

When did this thread degenerate into another "idling is bad, don't do it" mounds of drivel? I was trying to get some real data on how much fuel is actually used by idling vehicles. We all know it's more than zero, can we move on?
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giwan
Champion Author Michigan

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Message Posted: May 22, 2013 1:52:00 PM

Idling wastes enough fuel that newer cars will all have an auto start stop feature.
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PaylessKY
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Message Posted: May 22, 2013 1:28:43 AM

Idling wastes fuel. If you are going to set more than 5 minutes shut off the engine.
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Jmac2008
Champion Author Missouri

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Message Posted: May 22, 2013 1:07:57 AM

just shut it off and don't idle
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IAMCANADIAN73
Champion Author Ontario

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Message Posted: May 22, 2013 12:05:39 AM

Yep
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IAMCANADIAN73
Champion Author Ontario

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Message Posted: May 22, 2013 12:05:31 AM

Yes
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HotRod10
Champion Author Wyoming

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Message Posted: May 21, 2013 12:55:21 PM

Thanks Ryan!

Houckster, I ran the numbers you gave assuming averages of 7.5% and 12.5%, respectively. I used an average driving speed of 27 mph from your single tank info [217.1miles / (9.519hrs-1.523hrs) = 27.15mph]. The big assumption is that your mileage while driving was the same for both cases, but some assumption of mileage is necessary, otherwise there are too many variables in the equation. Anyway, with those assumptions your mileage without idling is 21.47mpg and your fuel consumption at idle is 1.33 gph (1.16 gph for the single tank). That's more than 3 times what Ryan just posted for warm-idle consumption on a V6, and more than 10 times the warm-idle consumption I observed and what was reported at MetroMPG for a 1.0L.
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Ryan456789
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Message Posted: May 21, 2013 3:09:35 AM

On a cold start on a cold day my V6 engine will use about 0.60gph to idle, once its all warmed up and running properly its about 0.40gph
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sagnat
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Message Posted: May 21, 2013 1:24:00 AM

**Thanks for your input, sagnat. If you could add the engine size, fuel type, and whether it was warm or cold idle, that would give us a fuller picture. **

Engine size - 2.0 litre Turbo Diesel. The fuel usage is a warm idle, never paid attention to idle consumption when cold but I'll try to remember to check it cold.
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Houckster
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Message Posted: May 20, 2013 4:10:44 PM

. . .to really nail this down? Your fuel consumption and miles or more exact mileage for your "normal" condition (the 10.7% idling case) would complete the picture.
_____
In actual driving, so many other variable can overshadow the effect of idling time on mileage that these figures should be taken with a grain of salt.

That said, I have 279 refuels in the database and 198 of them have idle time in the 5-15% range.

In the 5-10% range, I have 17,958.5 miles that required 903.567 gallons of fuel. The MPG is 19.875.

In the 10-15% range , I have 19,826.8 miles that required 1046.225 gallons of fuel. The MPG is 18.951.

I should note that the refuels were for driving events that did not include trips where the amount of idling would be very low.

I hope this helps.
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mybigtruck
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Message Posted: May 20, 2013 10:27:29 AM

That's right. All new diesels including buses and semis since 2008 have a Diesel Particulate Filter (DPF) ie, soot filter. Notice no more black tailpipes and smoke belching out...

Once the filter fills up, a regeneration process starts by injecting raw fuel out the exhaust. It burns in the CAT which superheats the exhaust upwards of 800-1000F and sends it into the DPF burning the soot. The soot in the DPF burns upwards of 1200-1250F. This reoccurs every 200-300miles and last anywhere from 15-30minutes with my driving habits.

When regen is taking place, I'm a moving blowtorch...don't be standing behind my tailpipe!!

All of the fuel economy that diesels used to enjoy are gone with this regen process. I calculated about a 5-6% fuel economy penalty. Needless to say, diesels now run much cleaner than gassers wrt to emissions.
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HotRod10
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Message Posted: May 20, 2013 9:58:49 AM

Thanks mybigtruck (@ 8100 lbs empty, your name definitely fits); .25gal/hr is less than I would've guessed for that size engine, especially a newer one with the emission controls that kick up the idle periodically to mitigate soot buildup. Yours does that, right?
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HotRod10
Champion Author Wyoming

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Message Posted: May 20, 2013 9:51:09 AM

Again, my apologies Houckster. My jab was meant as a joke; we have discussed, debated and argued enough I thought it was ok, but I didn't consider what others might think reading it.

thanks for the detailed info. Could I bother you for one more piece of information to really nail this down? Your fuel consumption and miles or more exact mileage for your "normal" condition (the 10.7% idling case) would complete the picture.
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mybigtruck
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Message Posted: May 18, 2013 10:28:49 AM

"I use a scanner in my diesel and my fuel consumption rate at idle while in 'drive' is the same as when I'm cruising about 25-30mph."

"Would you perhaps share what that fuel consumption rate is, mybigtruck?"

'10 F350, 6.4L diesel. 8100lbs empty with a full tank of fuel.

I seem to remember it was running approx 0.25gal/hr idling in 'drive', with no loads such as A/C. It drops to 0.15gal/hr idling in 'park' or 'idle'. Cruising in 3rd gear runs about the same 0.25gal/hr at 25-30mph with no load in the back. Of course it jumps if I'm on the pedal

This was using an AutoEnginuity scanner.

In general, my fuel consumption rate runs 1.7-2gal/hr in operation given my driving habits.

I didn't pay much attention when it was cold

[Edited by: mybigtruck at 5/18/2013 10:32:28 AM EST]
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Houckster
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Message Posted: May 17, 2013 11:06:26 AM

ME: "You may have started this thread but no one is under any obligation to answer exactly as you wish. People can post however they wish and as often as they wish."

HOTROD10: ...and I can poke fun at them as I wish when I think they've posted something that doesn't add to the discussion at hand.
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If you were poking fun, it sure didn't come through. If others were to read your comment, most would not see any humor whatsoever.
*****
ME: "So . . . if you want the additional information you requested, you can ask nicely!" Just because you were polite in the OP doesn't mean you can turn troll thereafter."

HOTROD10: If you want to have a pity party and withhold your information, that's up to you. I apologized already; I'm not going to beg.
_____
No one wants your pity and I'm not asking you to beg, just to ask nicely. If you had asked for more complete information as you did with SAGNAT, we wouldn't be having this discussion.
_____
Now hoping to get back on a proper footing, here is the best information I can provide:

The total amount of engine run time was 9.519 hours and 1.523 hours of that was spent idling. That's 16% of run time compared to a normal 10.7%. 217.1 miles required 11.886 gallons of fuel.
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HotRod10
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Message Posted: May 17, 2013 9:36:47 AM

Thanks for your input, sagnat. If you could add the engine size, fuel type, and whether it was warm or cold idle, that would give us a fuller picture.
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HotRod10
Champion Author Wyoming

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Message Posted: May 17, 2013 9:30:58 AM

"You may have started this thread but no one is under any obligation to answer exactly as you wish. People can post however they wish and as often as they wish."

...and I can poke fun at them as I wish when I think they've posted something that doesn't add to the discussion at hand.

"So . . . if you want the additional information you requested, you can ask nicely!" Just because you were polite in the OP doesn't mean you can turn troll thereafter."

If you want to have a pity party and withhold your information, that's up to you. I apologized already; I'm not going to beg.
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sagnat
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Message Posted: May 17, 2013 4:19:20 AM

I'm running Torque Pro and my idling consumption shows to be about .3 gallons/hour IIRC.
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Houckster
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Message Posted: May 16, 2013 6:10:28 PM

HOTROD10 wrote: Thank you for that completely useless bit of information, Houckster. If you would care to tell us the actual time idling, the gallons to fill up, and what your exact mileage was on the previous tank, then we might actually learn something.
_____
This is a lighthearted jab? Sorry, what is is extremely abrasive and heavy-handed. And there was not need for it. You may have started this thread but no one is under any obligation to answer exactly as you wish. People can post however they wish and as often as they wish.

So . . . if you want the additional information you requested, you can ask nicely!" Just because you were polite in the OP doesn't mean you can turn troll thereafter.

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HotRod10
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Message Posted: May 16, 2013 6:02:48 PM

Who's got their panties in a wad now, Houckster?

I'm sorry I offended you, I didn't mean to. It was a jab at your vague response, but it meant as a lighthearted jab.
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Houckster
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Message Posted: May 16, 2013 5:27:53 PM

HOTROD: If you wanted more information all you had to do was ask for it properly. Whether or not I provided the information you wanted gives you NO justification for the putrid remarks you made. Get your act together and quit acting stupid.

[Edited by: Houckster at 5/16/2013 5:28:52 PM EST]
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HotRod10
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Message Posted: May 16, 2013 5:19:19 PM

"One other thing HOTROD10, if you want the additional information you requested, you can ask nicely!"

I asked politely in the OP. Just because you chose to ignore what was asked for and opted to push your agenda instead, is not my problem. It doesn't matter to me whether you choose to contribute something of value to the discussion or not.

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HotRod10
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Message Posted: May 16, 2013 5:14:01 PM

"What got your panties in a wad?"

You hammering away at a point that has already been made on numerous occasions, including by you, and was never in dispute.

"As for the information being useless, get your act together. The exact number of gallons and mileage is irrelevant."

It's not irrelevant to what I asked, it's only irrelevant to your agenda and the point you wanted to make (again).

"I was simply demonstrating the effect of above average idling."

Houckster, you've been around long enough and we've been through these debates often enough that we are all aware that an idling engine uses more gas than an engine that is not running; that much should be obvious to everyone, especially you. My aim was to quantify the fuel usage at idle so that people can make informed decisions about what's worthwhile and what's too frivolous to concern themselves with.

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Houckster
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Message Posted: May 16, 2013 1:58:30 PM

One other thing HOTROD10, if you want the additional information you requested, you can ask nicely!

[Edited by: Houckster at 5/16/2013 2:00:12 PM EST]
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Houckster
Champion Author Atlanta

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Message Posted: May 16, 2013 1:51:06 PM

Thank you for that completely useless bit of information, Houckster. If you would care to tell us the actual time idling, the gallons to fill up, and what your exact mileage was on the previous tank, then we might actually learn something.
_____
What got your panties in a wad?

As for the information being useless, get your act together. The exact number of gallons and mileage is irrelevant. I was simply demonstrating the effect of above average idling. Sheesh!!!!


[Edited by: Houckster at 5/16/2013 1:56:24 PM EST]
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HotRod10
Champion Author Wyoming

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Message Posted: May 16, 2013 12:10:11 PM

"I use a scanner in my diesel and my fuel consumption rate at idle while in 'drive' is the same as when I'm cruising about 25-30mph."

Would you perhaps share what that fuel consumption rate is, mybigtruck?

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HotRod10
Champion Author Wyoming

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Message Posted: May 16, 2013 10:54:31 AM

"On my last tankful, I had a substantially greater than normal amount of idling, almost 50% more. Normally around town, I'll get about over 19 MPG on my Ranger. On this tankful it was 18.265. Idling does hurt."

Thank you for that completely useless bit of information, Houckster. If you would care to tell us the actual time idling, the gallons to fill up, and what your exact mileage was on the previous tank, then we might actually learn something.
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Houckster
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Message Posted: May 16, 2013 10:11:46 AM

"I bet having the A/C running affects the amount of fuel used at idle also"
____
Any time the engine has to work harder, it will use more gas. That's one of the reasons we're starting to see things like electric power steering. Eventually, I think the A/C will run off the electrical system if the OEMs can get a fuel efficiency improvement.
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OceanArcher
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Message Posted: May 15, 2013 12:28:27 PM

I bet having the A/C running affects the amount of fuel used at idle also
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Wanda127
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Message Posted: May 15, 2013 12:18:28 PM

I don't have a fuel monitoring device but I know mileage goes down when I idle a lot.
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Houckster
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Message Posted: May 15, 2013 9:11:47 AM

On my last tankful, I had a substantially greater than normal amount of idling, almost 50% more. Normally around town, I'll get about over 19 MPG on my Ranger. On this tankful it was 18.265. Idling does hurt.
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eyegotgas2
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Message Posted: May 14, 2013 4:02:47 AM

Don't have a gauge but if the engine is running it is using fuel. Fuel is getting to valuable to prewarm a vehicle.
I could see it more popular in colder temperatures.
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mybigtruck
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Message Posted: May 14, 2013 3:54:40 AM

I use a scanner in my diesel and my fuel consumption rate at idle while in 'drive' is the same as when I'm cruising about 25-30mph.

If stuck at a long light but not long enough to shut down the engine, I'll throw it in neutral. That cuts fuel rate down quite a bit.
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HotRod10
Champion Author Wyoming

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Message Posted: Mar 13, 2013 9:59:16 AM

That's good advice, beachd8; although no one on this thread has suggested anything of the sort. I'm just trying to gather some hard data on fuel consumption at idle, since there are many estimates getting thrown around about how expensive it is (mostly by environmental groups) to warm up your car.

Unless larger engines use many times the fuel that the 1.0L and 1.8L engines we have data for, the fraction of a cent saved by shutting off the engine at a red light would indeed not be worth the risks, or the wear and tear on the starter, IMHO.
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beachd8
Champion Author Orange County

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Message Posted: Mar 13, 2013 1:41:43 AM

The possibility of getting rear ended for turning off your car at a red light & having a driver behind you not notice outweighs any potential savings IMHO.
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