Why do i get terrible gas mileage?
#62
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**UPDATE**
Just filled up again since i last posted my results...
243.0 miles on the trip.
Filled her up 13.641 gallons...
243.0/13.641 = 17.8 mpg
Looks like I picked up a WHOLE MPG!!
niiiiiiice...
Just filled up again since i last posted my results...
243.0 miles on the trip.
Filled her up 13.641 gallons...
243.0/13.641 = 17.8 mpg
Looks like I picked up a WHOLE MPG!!
niiiiiiice...
#63
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Do you ever drive any highway? that still seems low? I use Fuelly.com to track mileage and right now I am sitting at 22mpg avg (and that includes a lot of playing around, passing people constantly, a few triple digit runs, etc)...
BTW not sure whats up with your tank but I've been on the E for a while (20+ miles with the check guages lit) and the most I put in the car is 13 gallons... my normal fill up on or near the E mark is 12.xx gallons.
BTW not sure whats up with your tank but I've been on the E for a while (20+ miles with the check guages lit) and the most I put in the car is 13 gallons... my normal fill up on or near the E mark is 12.xx gallons.
#64
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Actually i think yours is abnormal... but in a good way. Ive got like 30-50 miles once my light goes off before shes out. Usually once i see it go off, and get pulled over im around 14.25 gallons to fill. Its just the little sensor on the float... you can bend it to change when the light comes on.
Last edited by xxrillixx; 11-20-2008 at 08:57 AM.
#66
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its not the PCM going lame... its just not getting a good read out from the O2's, usually because they get blocked up. The O2's are constantly reading and adjusting the amount of fuel according to your levels in the exhaust... when its lagging its not cutting and adding fuel like it should. PCM is actually getting faulty data, you lose performance and gas mileage.
#67
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I get around 21-23 mpg mixed city/highway (highway is 55 mph, has lights). On the way to Phoenix, with no cruise controll, having many times going past 100 mph, and cruising with rpms at around 2200, I got 28 mpg. I actually get better mpg with my 4.10s then I did when I had my 3.42s. Don't know how, I guess driving habbits, but with the 3.42s I was at like 18-19.
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The car is 100% stock. I do probably 95% city driving. Good call on the O2's. I didn't even think about this. I'm not throwing any codes at all...? How many should I replace?
#69
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Well, here is what I can tell you about my 99Z, A4, 3.23, and stock sized rims/tires. When the car was new, and bone stock, I would get 22 combined city/highway, with best of 29-30 strictly highway, on long trips, at 70-75mph. Now days, I get a maximum of 25-26 strictly highway, with the average still being around 21-22. I attribute this drop to several things:
1. I have ALOT more miles on it now (180k+)
2. The small mods I have made: cowl hood, cat-back, and free ram-air, with no tuning.
3. All fuel is now a mixture of ethanol and gasoline. Depending on where you live, the ratio can be higher or lower. In my area, it is now 10% ethanol.
For those of you who have changed tires or gears, did you have the speedo re-calibrated? If not, your odometer is wrong, and so is the trip OD. The best way I know to check is on a long trip, watch the mile marker signs for at least 20-30 miles, and compare your odometer.
KevinD
1. I have ALOT more miles on it now (180k+)
2. The small mods I have made: cowl hood, cat-back, and free ram-air, with no tuning.
3. All fuel is now a mixture of ethanol and gasoline. Depending on where you live, the ratio can be higher or lower. In my area, it is now 10% ethanol.
For those of you who have changed tires or gears, did you have the speedo re-calibrated? If not, your odometer is wrong, and so is the trip OD. The best way I know to check is on a long trip, watch the mile marker signs for at least 20-30 miles, and compare your odometer.
KevinD
Last edited by kmdracer; 11-20-2008 at 12:18 PM. Reason: mileage type in wrong
#71
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Well, here is what I can tell you about my 99Z, A4, 3.23, and stock sized rims/tires. When the car was new, and bone stock, I would get 22 combined city/highway, with best of 29-30 strictly highway, on long trips, at 70-75mph. Now days, I get a maximum of 25-26 strictly highway, with the average still being around 21-22. I attribute this drop to several things:
1. I have ALOT more miles on it now (180k+)
2. The small mods I have made: cowl hood, cat-back, and free ram-air, with no tuning.
3. All fuel is now a mixture of ethanol and gasoline. Depending on where you live, the ratio can be higher or lower. In my area, it is now 10% ethanol.
For those of you who have changed tires or gears, did you have the speedo re-calibrated? If not, your odometer is wrong, and so is the trip OD. The best way I know to check is on a long trip, watch the mile marker signs for at least 20-30 miles, and compare your odometer.
KevinD
1. I have ALOT more miles on it now (180k+)
2. The small mods I have made: cowl hood, cat-back, and free ram-air, with no tuning.
3. All fuel is now a mixture of ethanol and gasoline. Depending on where you live, the ratio can be higher or lower. In my area, it is now 10% ethanol.
For those of you who have changed tires or gears, did you have the speedo re-calibrated? If not, your odometer is wrong, and so is the trip OD. The best way I know to check is on a long trip, watch the mile marker signs for at least 20-30 miles, and compare your odometer.
KevinD
#72
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Actually i think yours is abnormal... but in a good way. Ive got like 30-50 miles once my light goes off before shes out. Usually once i see it go off, and get pulled over im around 14.25 gallons to fill. Its just the little sensor on the float... you can bend it to change when the light comes on.
#75
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Maybe its just the stock tune on certain cars? I didnt read all of this thread, but my car is stock and it seems to only get like 18 mpg when i drive like a old lady shifting at 2k, and its not like im luggin the motor at all, but it just seems that it should be better.
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Maybe its just the stock tune on certain cars? I didnt read all of this thread, but my car is stock and it seems to only get like 18 mpg when i drive like a old lady shifting at 2k, and its not like im luggin the motor at all, but it just seems that it should be better.
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i got a 2002 camaro z28 with an a4 and 85k miles and i get around 200-240 a tank most the time but on the freeway i took a road trip and actually got 372 out of a full tank and im talking all 15.5 gallons.