MPG loss???
07-22-2010, 11:57 AM
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MPG loss???
I recently installed Stillen exhaust and upgraded to 20" rims. I noticed that my MPG gauge is a LOT lower than normal of my daily driving. I used to get around 20-21mpg now I'm avg 15mpg. I haven't actually calculated it myself but just going on the gauge that came with the car.
Is that gauge not accurate anymore b/c of the increase in wheel size or is my MPG really that bad b/c of the exhaust/rims now?
Is that gauge not accurate anymore b/c of the increase in wheel size or is my MPG really that bad b/c of the exhaust/rims now?
07-22-2010, 12:59 PM
#3
When you increased the size of the rim the tire sidewall should have gone down so the overall size of your wheels didn't change.
Most likely what is happening is the new wheels are heavier than the OEM ones. How many miles have you driven to get the gauge to show that?
There are so many factors that play into MPG. could be a different gas station, different driving habits, or even if you are doing several very short trips, that will really kill your MPG
Most likely what is happening is the new wheels are heavier than the OEM ones. How many miles have you driven to get the gauge to show that?
There are so many factors that play into MPG. could be a different gas station, different driving habits, or even if you are doing several very short trips, that will really kill your MPG
07-22-2010, 01:32 PM
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Off topic but Highspeed...I just got back from SC...since when did all SC gas stations start posting up one gas price but at the pump they're all a few cents HIGHER! Isn't that false advertising?
When you increased the size of the rim the tire sidewall should have gone down so the overall size of your wheels didn't change.
Most likely what is happening is the new wheels are heavier than the OEM ones. How many miles have you driven to get the gauge to show that?
There are so many factors that play into MPG. could be a different gas station, different driving habits, or even if you are doing several very short trips, that will really kill your MPG
Most likely what is happening is the new wheels are heavier than the OEM ones. How many miles have you driven to get the gauge to show that?
There are so many factors that play into MPG. could be a different gas station, different driving habits, or even if you are doing several very short trips, that will really kill your MPG
Hearing it more nowadays? 
07-22-2010, 02:09 PM
#7
Figure your mileage the old fashioned way, divide actual miles traveled by actual gallons used. That is the only certain way to know your exact mileage, the computer is a little off for a variety of reasons. Mostly because it doesn't use an accurate amount of fuel in the calculation. That's why the gas gauge and distance to empty isn't really completely correct.
Fill up your tank. All the way. Reset your trip odometer. Drive until your next fill up. Fill up all the way again so you know you have a completely full tank. Note exactly how many gallons this takes. Divide the number of miles you've traveled by how many gallons of fuel it took to refill your tank completely. This is your accurate MPG number.
Fill up your tank. All the way. Reset your trip odometer. Drive until your next fill up. Fill up all the way again so you know you have a completely full tank. Note exactly how many gallons this takes. Divide the number of miles you've traveled by how many gallons of fuel it took to refill your tank completely. This is your accurate MPG number.
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07-22-2010, 02:50 PM
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Yeah...haven't gone a full tank yet since the additions so I havne't had a chance to calculate...just wanted to know if anyone else had this issue.
Figure your mileage the old fashioned way, divide actual miles traveled by actual gallons used. That is the only certain way to know your exact mileage, the computer is a little off for a variety of reasons. Mostly because it doesn't use an accurate amount of fuel in the calculation. That's why the gas gauge and distance to empty isn't really completely correct.
Fill up your tank. All the way. Reset your trip odometer. Drive until your next fill up. Fill up all the way again so you know you have a completely full tank. Note exactly how many gallons this takes. Divide the number of miles you've traveled by how many gallons of fuel it took to refill your tank completely. This is your accurate MPG number.
Fill up your tank. All the way. Reset your trip odometer. Drive until your next fill up. Fill up all the way again so you know you have a completely full tank. Note exactly how many gallons this takes. Divide the number of miles you've traveled by how many gallons of fuel it took to refill your tank completely. This is your accurate MPG number.
07-22-2010, 03:43 PM
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I've been getting horrible mileage lately. Around 18 mpg. It has been 70% city driving 30% highway miles. I am thinking it is because it has been really hot and the engine isn't making as much power. I get on it once in awhile but I don't feel like i'm driving the car particularly hard.
07-22-2010, 04:31 PM
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