Poor Gas Mileage?
#16
I was noticing the same thing the other day. I was driving around and i was like my gas mileage is horrible. Then i thought like one of those gothic kids that think the government is trying to enslave us...and i was like maybe they are putting something in the fuel to make it less efficient lol.
Now with your "evidence" i think my case is true!
-Sean
Now with your "evidence" i think my case is true!
-Sean
#17
#18
Originally Posted by jimmyc13
Are you serious? How is that "the worst type of warm"? I religiously do not drive my car until the engine is warm (with the thought of it being bad for the car to drive it cold). I know I've seen other threads on here that mentioned you can start driving after 30 seconds of startup, but how can letting the car idle be bad? Very curious! ![Confused2](https://g35driver.com/forums/images/smilies/confused2.gif)
![Confused2](https://g35driver.com/forums/images/smilies/confused2.gif)
#20
Originally Posted by jimmyc13
Are you serious? How is that "the worst type of warm"? I religiously do not drive my car until the engine is warm (with the thought of it being bad for the car to drive it cold). I know I've seen other threads on here that mentioned you can start driving after 30 seconds of startup, but how can letting the car idle be bad? Very curious! ![Confused2](https://g35driver.com/forums/images/smilies/confused2.gif)
![Confused2](https://g35driver.com/forums/images/smilies/confused2.gif)
![Icon38](https://g35driver.com/forums/images/smilies/icon38.gif)
1) When the engine is cold, it's running extremely rich and inefficiently. Letting it idle for a prolonged period of time uses excessive amounts of fuel. The quickest way to warm up the motor is to start driving and you'll use less fuel doing it.
2) Excessive rich conditions can lead to fouled cats because the cats get drenched in fuel and since you're not driving yet, they take much longer to light off.
3) Letting the motor warm up at an extended idle doesn't warm up other important components like tranny and diff fluid. Many people think since the motor is warm, they can drive like normal without considering the tranny/diff. This could be a costly mistake in the long term.
4) Letting the motor warm up by idle can lead to hot and cold spots on the motor. Oil doesn't get distributed as effectively, especially on the upper portion of the motor like the VTCs and rockers.
#22
Once I get a good mpg baseline (recording fillups and calculating mileage now), I'm going to try this stuff:
![](http://www.amsoil.com/StoreFront/images/api_bottle_Guarantee.jpg)
http://www.amsoil.com/storefront/api.aspx
"Improves fuel mileage an average of 2.3% and up to 5.7%. Reduces emissions such as hydrocarbons (HC) up to 15%, carbon monoxide (CO) up to 26% and nitrous oxides (NOx) up to 17%. Restores power and performance. Reduces the need for costly higher octane fuel. Reduces noise from carbon rap and pre-ignition. Offers better vehicle drivability and smoother operation."
Moneyback guarantee, so why not?
+1 on the long idling, not necessary and a waste of gas.
![](http://www.amsoil.com/StoreFront/images/api_bottle_Guarantee.jpg)
http://www.amsoil.com/storefront/api.aspx
"Improves fuel mileage an average of 2.3% and up to 5.7%. Reduces emissions such as hydrocarbons (HC) up to 15%, carbon monoxide (CO) up to 26% and nitrous oxides (NOx) up to 17%. Restores power and performance. Reduces the need for costly higher octane fuel. Reduces noise from carbon rap and pre-ignition. Offers better vehicle drivability and smoother operation."
Moneyback guarantee, so why not?
+1 on the long idling, not necessary and a waste of gas.
Last edited by Swivel; 12-16-2008 at 12:27 PM.
#25
So glad I read this thread. I was beginning to freak out. Thought something was seriously wrong. Definitely going to check the air filter. I know gas mileage varies but this last time around there has been a significant change. I fueled up today and I noticed "10% eythanol" on the gas pump. Typically I get over 300+ miles out of a tank and recent filled up at 250-260.
#26
#27
Keep in mind... when your gas light comes on you generally have 5 gallons left.
The gas tank is 20 Gal. I've gone close to 500 miles in my car. 5AT. I got 28 mpg one trip.
I agree totally with not spending too much time warming up your engine in the driveway on idle. If you do that you should notice that your tranny shifts much harder because it is not warmed up yet.
The gas tank is 20 Gal. I've gone close to 500 miles in my car. 5AT. I got 28 mpg one trip.
I agree totally with not spending too much time warming up your engine in the driveway on idle. If you do that you should notice that your tranny shifts much harder because it is not warmed up yet.
#30
10% ethanol is the standard year round; its nothing new.
I agree, it's not great to warm a car up by idling due to low oil pressure combined with thick oil. It's probably not detrimental but I'd avoid it if you can.
Fluctuation in gas mileage is pretty normal, especially in winter. The cooler air and higher atmospheric pressure do cause an increase in consumption. However this does equate into a slight increase in power. The stat I've heard is about 2% HP increase for ever 10 degrees C.
I agree, it's not great to warm a car up by idling due to low oil pressure combined with thick oil. It's probably not detrimental but I'd avoid it if you can.
Fluctuation in gas mileage is pretty normal, especially in winter. The cooler air and higher atmospheric pressure do cause an increase in consumption. However this does equate into a slight increase in power. The stat I've heard is about 2% HP increase for ever 10 degrees C.