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Help really bad gas mileage

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Old 03-12-2010, 12:01 PM
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Help really bad gas mileage

Whats up fellas. For some reason I am getting really bad gas mileage on my X. I've had the car for 5 years now and only 27k miles on her. I get an average of 100 miles a tank. This has been happening for the pass 3-4 weeks. The car only drives locally now alot of stop and go with lights and stop sign. At first I thought it was my wife but I have been driving it and still the same. The car is back to stock hight and stock exhaust. Any advice.
 
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Old 03-12-2010, 12:08 PM
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Oil changes? maybe too soon for spark plugs. I dont think that much too much stop and go could give you 100 miles to the tank. Unless it's not filling up all the way.
 
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Old 03-12-2010, 12:08 PM
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Reset the ecu and drive like a grandma. You should try cleaning the maf and applying assorted chemicals to clean out your car, but you have low miles so really not sure.
 
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Old 03-12-2010, 12:11 PM
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Yeah and check your air filter while you're at it.
 
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Old 03-12-2010, 12:13 PM
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check the following: air filter, MAF to ensure it is not damaged/dirty, fuel system cleaning. Diagnostics may tell you a story.
 
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Old 03-12-2010, 12:17 PM
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Are you still on factory warranty?
 
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Old 03-12-2010, 01:14 PM
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I cleaned the air filter amd changed the oil last week. I'm out of warranty. I was planning on taking it to the dealer for a diagnostics check.
 
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Old 03-12-2010, 02:00 PM
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If I drive pretty hard... WOT alot, will this yield around 13mpg or is my car coming across some problems?
 
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Old 03-12-2010, 02:57 PM
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Originally Posted by Gnightsedan
If I drive pretty hard... WOT alot, will this yield around 13mpg or is my car coming across some problems?
Man, I thought I got bad MPG sometimes with spirited driving. Is it that bad? If so I would get that looked at. Premium adds up
 

Last edited by Ludafish; 03-12-2010 at 03:08 PM.
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Old 03-12-2010, 03:05 PM
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Originally Posted by Gnightsedan
If I drive pretty hard... WOT alot, will this yield around 13mpg or is my car coming across some problems?

That;s about what you'll get if you are always flooring it
 
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Old 03-12-2010, 03:11 PM
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maybe the tank is not filling all the way up, I've heard of some people complain about that....
 
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Old 03-13-2010, 10:41 AM
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^ the tank not filling up all the way is only refering to the last 1/4. We have 18.5 or 20 gal tanks... worst case you only get 10 gals in. 100 miles at 10 gals is 10MPG. for someone not WOT and etc and trying to get good MPG that is insane.

when was the last time your car was aligned and had stock wheels on it.

something would be wrong. A free cheap way before going to the dealership and spend the money is check for CEL yourself. if none is present then yea by all means send the car to the dealership or some shop to have it looked at. worst i ever did was like 220 miles and that was the first couple months i had it and i went crazy WOT now i get 300 or so and thats when the light comes on.


These cars aren't going to MPG king but they should be in the upper teens.
 
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Old 03-13-2010, 11:13 AM
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you need to calculate your gas mileage. Fill it up as much as you can, reset the trip comp.. and run her around, then fill it up.. divide the numbers and find out how much you put in vs the miles you ran.
 
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Old 03-13-2010, 11:21 AM
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O2 sensor?
 
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Old 03-13-2010, 02:25 PM
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Originally Posted by jmueller
you need to calculate your gas mileage. Fill it up as much as you can, reset the trip comp.. and run her around, then fill it up.. divide the numbers and find out how much you put in vs the miles you ran.
Good point, but this would only help him if the car stops filling up at the same point all the time. Guess it would be hard to know that though, as it seems like his car doesn't fill up all the way or his gauge is off. Yeah, I agree with the other comments above, 100 miles on a tank isn't right, no matter how dirty your air filter is or how bad your plugs are. Maybe it's your fuel senders? I think that's what reads the gas level in the tank vs. what's on your fuel gauge.

Good luck, let us know when it's resolved and what the culprit is!
 


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