MPG starting to suffer? What should I look at?
08-29-2007, 09:08 PM
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MPG starting to suffer? What should I look at? As of right now, I get 120ish miles on half a tank of gas, however after the needle passes the half way mark and starts going to the left, the guage goes FAAAST, as in that last "half tank" will take me 50 miles, tops. Whats wrong with this? The gas light comes on before it even gets to the empty line. Is 170 miles on a tank of gas normal? I think it should get a little more then this.
Its an A4, trans an engine have 144,440 miles on them, I have LT headers, Y pipe, no cat, and Borla exhaust, along with a tune.
Its an A4, trans an engine have 144,440 miles on them, I have LT headers, Y pipe, no cat, and Borla exhaust, along with a tune.
08-30-2007, 02:30 AM
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I would look at replacing your 02 sensors if they are old, and your plugs and plug wires if they are ageing as well. Did you have it checked for codes? Mine has tripped codes without having a check engine light come on before. Autozone, ECT will check your car for codes free.
Last edited by BOONE; 08-30-2007 at 02:41 AM.
08-30-2007, 05:19 PM
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Don't go by miles per tank on a half tank of gas. Fill it up, drive it around to about half a tank, fill it again at the same pump, then do the math and see what your actual MPG is. If the gauge is going from 1/2 to empty in 50 miles something's wrong with the gauge or sending unit IMO.
08-30-2007, 05:21 PM
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Originally Posted by 94_9C1
As of right now, I get 120ish miles on half a tank of gas, however after the needle passes the half way mark and starts going to the left, the guage goes FAAAST, as in that last "half tank" will take me 50 miles, tops. Whats wrong with this? The gas light comes on before it even gets to the empty line. Is 170 miles on a tank of gas normal? I think it should get a little more then this.
Its an A4, trans an engine have 144,440 miles on them, I have LT headers, Y pipe, no cat, and Borla exhaust, along with a tune.
Its an A4, trans an engine have 144,440 miles on them, I have LT headers, Y pipe, no cat, and Borla exhaust, along with a tune.
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09-02-2007, 12:14 AM
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I don't think your milage is going down on the bottom half of the tank and back up on the top half. My 97 Trans Am has done this since I got it. I get around 250 miles to a tank, 18-20 MPG depending on how much time my foot stays on the floor. I always thought it was the shape of the gas tank, I've never seen it out of the car. I haven't tried this my self, but you could see how much gas it takes to top off the tank from half full. I suspect it will be more than half the capacity of the tank.