Took 1/4 Tank for 25 miles!??!?
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Took 1/4 Tank for 25 miles!??!?
So my vehicle it seems has been having some issues with getting mileage out of the tank since I purchased it back in October.
Last tank after filling full I got about 175 miles out of it, which seems to be pretty below average.
Now I have driven about 25 miles over the course of a few days of highway and city mixed on a new full fillup. My fuel gauge level is about on the 3/4 tank full mark.
So you would assume that the car has a fuel leak. I've checked underneath from the fuel rails back to the tank and nothing is leaking. The car has about 42,000 miles and so far I have cleaned the air filter, replaced the fuel filter, seafoamed the fuel tank, sprayed the MAF, checked tire psi, and looked for vacuum leaks.
My next step would be replacing the plugs and having the injectors checked. Otherwise I would assume maybe an injector is stuck open or there's a tunning issue that needs to be dealt with? The car doesn't smell like it's burning rich. Kind of at a loss at the moment. Ideas?
Last tank after filling full I got about 175 miles out of it, which seems to be pretty below average.
Now I have driven about 25 miles over the course of a few days of highway and city mixed on a new full fillup. My fuel gauge level is about on the 3/4 tank full mark.
So you would assume that the car has a fuel leak. I've checked underneath from the fuel rails back to the tank and nothing is leaking. The car has about 42,000 miles and so far I have cleaned the air filter, replaced the fuel filter, seafoamed the fuel tank, sprayed the MAF, checked tire psi, and looked for vacuum leaks.
My next step would be replacing the plugs and having the injectors checked. Otherwise I would assume maybe an injector is stuck open or there's a tunning issue that needs to be dealt with? The car doesn't smell like it's burning rich. Kind of at a loss at the moment. Ideas?
#2
It could be the plugs , also how long are your average trips with the car? If you make a ton of short trips without allowing the car to reach operating temperatures it could drastically hurt your fuel millage b/c engines only operate at maximum efficiency when its within its designed operating temperature.
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ya... by the time I reach work it's about getting up to full operating temperature and out of open loop. this is about 1 mile of street driving and 2 miles of highway driving
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do you do the math by how many gallons vs. miles you drive to see actuall MPG or just going off the gauge? could just be a faulty or bent sending unit from having the pump changed... you never said acutal mpg so thats y im tossing this out there
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ok well I forgot to mention ya... I kept track of my MPG last tank by tracking the odometer and trip at the same time to make sure there was no difference.
I got 178 miles out of my last tank and put about 12.9 gallons in it which is about 13.8 MPG
Doing the same this tank and also using this site here to double check: http://www.mpgtune.com/index.php
I got 178 miles out of my last tank and put about 12.9 gallons in it which is about 13.8 MPG
Doing the same this tank and also using this site here to double check: http://www.mpgtune.com/index.php
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I have a mini stalled A4 (2400). LT's, pulley, ls6 intake. I used to get about 220-230 miles per tank and if I work the nozzel, I can get 16.9 gallons in it.
I just tuned (by "12secss" - George Lara) my rich running car (that didn't smell rich, but my rear bumper showed it) and now on my 2nd tank I'm averaging 270 a tank. That's 40-50 mile per tank difference. I'm loving it now. Too bad I didn't do the tune 2 years ago.
Edit: Oh yeah, and i've got 3.73's out back too!
I just tuned (by "12secss" - George Lara) my rich running car (that didn't smell rich, but my rear bumper showed it) and now on my 2nd tank I'm averaging 270 a tank. That's 40-50 mile per tank difference. I'm loving it now. Too bad I didn't do the tune 2 years ago.
Edit: Oh yeah, and i've got 3.73's out back too!
Last edited by Sommer86; 03-24-2010 at 04:58 AM. Reason: edit
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I just did 17mpg, mostly city driving with several short trips. That's an A4 car with 96k miles on the stock plugs too. I usually get as high as 24-26 with mixed city and highway. I've never done straight highway though.
I would say you have an issue somewhere.
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it is pissing me off since it's drinking fuel pretty bad
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That sucks. . . . I say it should be above 20, at least.
The only thing I can think of is to check all your basic crap. Fuel filter, air filter, plugs, make sure it's not throwing codes(I know you said you already did). . . . .
I don't know where else to look. . . . .
You could also check your compression. . . . I just don't know where else to look.
The only thing I can think of is to check all your basic crap. Fuel filter, air filter, plugs, make sure it's not throwing codes(I know you said you already did). . . . .
I don't know where else to look. . . . .
You could also check your compression. . . . I just don't know where else to look.
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P.S O2 will not throw a code until they are very bad so it could be slow switching but just above the amount need to keep the code from being thrown. If you have access to a scan tool you can look at them and see how fast they are switching.
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With my old commute, it would be like clockwork, first 1/4 tank would always get me exactly 115 miles. That was with 75% highway and 25% city on that route.
I hear about lots of M6 guys doing 29+ MPG with pure highway driving. I beleive that, seeing as my A4 has done mid-20s with some city mixed in.
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Something isn't right. I average about 210 miles per tank (18.5mpg) with a stock A4 Formula. I would expect a m6 to do better than that. Check the basics first and see whats going on.
How do some of you get 16+ gallons in your tank? Everything I have read says I should have a 16.8 gallon tank, but even if I let it go to E and the light comes on I can barely get 12.5 gallons in mine. Either I have a 4 gallon reserve or a 13 gallon tank like my LT1 had.
How do some of you get 16+ gallons in your tank? Everything I have read says I should have a 16.8 gallon tank, but even if I let it go to E and the light comes on I can barely get 12.5 gallons in mine. Either I have a 4 gallon reserve or a 13 gallon tank like my LT1 had.