Is there a way to determine the gas "mileage" while idling? For example, if I were to sit in a parking lot for 30 minutes with my car idling, how much gas would I burn? I have a '98 LX if that matters. During normal usage in the Summer, for example, I get on average 37 mpg.

Thanks,

Scott

 

http://www.solveyourproblem.com/save...-mileage.shtml

dont idle lol

 

At idle you travel no distance, so your mpg would also be zero at idle. As to how much gas is burned per unit time at idle, I don't know the answer.

 

If you know you're going to Idle more then 10 seconds turn off your car because you use about 10 seconds worth of fuel just starting your car. I personally don't do this because I'm not a gas saving nut, but I know it helps plus I don't see it being easy on your starter.

 

Well, thanks for the replies, but so far none of this helps me.

Yes, Ron, I realize that at idle my mpg will be zero. That's why I put the word mileage in quotes.

I guess I'll just cut to the chase. When I get to work in the morning, I take a nap in my car until I need to go in the building. It's usually about 30 minutes and I leave the car running for heat. I did this last winter starting in January, and it didn't seem to really affect my mileage. Now this winter, I'm down to 34 mpg from my normal 37 or 38.

I drive 68 miles each way to and from work. I fill up every other day, so I get four trips on fill ups. So that means that I idle in the parking lot two times for each fill up, or about one hour for each tank of gas.

And yes, I realize all of the negatives and downsides to doing this. For me it's worth the 30 minute nap. That's all not the point. I'm just trying to figure out about how much gas I am really wasting by doing this.

Can anyone else help?

 

Given that prolonged idling did not seem to have a measurable effect on mileage last winter, you may just need to do a basic tune up to restore the original higher gas mileage.

On the other hand, if you believe that 1 hour of idling is now reducing your mileage from 37-38 mpg to 34 mpg, you can estimate gas usage during idling using the information provided in your post above and simple math. The calculation indicates that 1 hour of idling uses about 0.6-0.8 gallons of gas.

Here's how to calculate:

The amount of gas used to drive 272 miles (2 work days of travel) when your mileage is 34 mpg (with 1 hour of idling) versus 37 mpg or 38 mpg (without idling) is 8 gallons, 7.4 gallons, or 7.2 gallons, respectively. Hence, 1 hour of idling requires around 0.6-0.8 gallons of gas.

 

haha you sleep in your civic... doesnt sound too comfortable

 

You could always hook up a remote fuel canister to your fuel rail and put 100ml of fuel in it and see how long it takes until the motor stops. Then divide the amount of time it took in minutes by the about of ML used (100). to find your fuel consumption at idle.

 

Well, that's actually what I'm trying to determine. It just so happens that I got new tires about the same time the weather got cold. So now I'm trying to determine if it's the tires or the idling. I guess I'll just have to wait until it's warm enough out that I don't have to run the car for heat. :-)

 

It's not that bad. I'm short (5'8"). I just recline the seat back, bend my knees up, and snooze.