View Full Version : Really bad gas mileage?
yayjohnny
05-17-2011, 11:13 AM
Last tank, I only got like 280 miles (18mpg?!) on a FULL tank. Half of it was city driving over a course of a week or something, but the other half was highway.
Today, I filled up all the way and am attempting to figure out how many miles I can get out of my tank. I feel like something is wrong because my MPG is freaking terrible.
Recently, just in idle or like, rolling... the trip computer is showing that 8mpg and only 300 miles for my tank. This is immediately right after I filled up all the way.
I recently changed:
spark plugs to NGK BKR7EIX
K&N drop in filter without the foam
cam follower replaced
http://imageshack.us/m/69/8263/dsc0153i.jpg
http://imageshack.us/m/94/3811/dsc0154ni.jpg
And I have a retarded "left parking light" "right parking light" errors in my dash everytime I turn the car on. But all lights seem functional?
Anybody have any insight on what might be happening? or is this normal?
i wish i got 280, i get about 200 on average. all city
mr_esmit
05-17-2011, 12:36 PM
The parking light might one of the contacts on the bulbs. Turn all your lights on and have some else step on the brakes.
As for the MPG, this has been a discussion topic for the ages. I can be a number of things including fuel filter, under/over gapped plugs, etc. I've given up on mine and learned to live with it. I actually get les MPG when I have maintenance done...
matthewb2795
05-17-2011, 12:39 PM
PCV is always a good thing to check out. Mine was failing and I didn't even know it. I was getting really bad gas mileage for a while but after replacing it my milage sky-rocketed.
yungcotter
05-17-2011, 12:56 PM
Try cleaning your maf sensor that helped my mileage. also check your fuel filter.
Satyroi
05-17-2011, 01:47 PM
It could also be the shitty enthanol they put in our gas? I noticed the drop in MPG years ago when they started adding a min 10% ethanol mixture. Combine that with Cali's 91 max octane grade and it just robs our engines peak performance.
B-Time
05-17-2011, 03:02 PM
http://www.audizine.com/forum/search.php?searchid=1035574
abccba
05-17-2011, 03:37 PM
http://www.audizine.com/forum/search.php?searchid=1035574
FAIL
mixtery
05-17-2011, 03:49 PM
yep I had a tank about a month ago that was almost all city and got about 19. My best tank was 25 mostly highway. I drive 3 times a week or else I'd be a PO' man these days.
this may be small and stupid, but when i finally realized a couple of my tires were way under the psi they needed, i got about 7-11 more mpg on my car. so maybe on top of the all the above things just make sure the tires got the right amount of air
b7kevin
05-17-2011, 05:34 PM
^^ it isn't stupid under inflated tires are a true MPG killer.
This has been covered but heres the main things:
MAF clean element.
Tire pressure (as stated).
Oil viscosity
Carbon build up
Air filter
Plugs
Fuel Grade
Fuel Filter
Dirty injectors
Coderedpl
05-17-2011, 05:41 PM
Honestly....that's about what I get 50/50 highway/city. Anywhere between 280-330. Depends on if i make additional trips or whatever.
b7kevin
05-17-2011, 06:01 PM
on my way to work stage 2+ I get 31 MPG at 65-70mph. 75-80 MPH i get 24-26 MPG. Stop and go traffic on the highway 9.7 MPG :-(
Nebone
05-17-2011, 08:58 PM
I get 400 to a full tank, which requires 16.5 gallons. 50/50 Highway/City
Sprode
05-18-2011, 07:24 AM
It could also be the shitty enthanol they put in our gas? I noticed the drop in MPG years ago when they started adding a min 10% ethanol mixture. Combine that with Cali's 91 max octane grade and it just robs our engines peak performance.
This is about as dense as ignorant statements can get.
Charles.waite
04-27-2012, 01:01 AM
Reviving this bad boy, my apologies!
Recently replaced my t-stat and got the intake runner flap and PCV extensions completed. My mpgs over the last 2 tanks have been 15.8 and 16 mpgs. Freaking awful. My 1.8t gets closer to 23 on the same commute and it had a number of issues that have been corrected recently.
I'm going to try to log the MAF tomorrow and see if it's reporting sane numbers. Could anyone tell me what normal MAF readings should be for a bone stock 2.0t? The thing is running great, it's just gulping fuel like its it's job. I'm at my wits end. My b6 is supposed to be my problem child, not my b7!
Also I feel stupid for contributing to a HELP MY MPGS SUCK thread but help a brotha out, apparently I'm no good at diagnosing my own problems!
Kipper984x
04-27-2012, 03:37 AM
Your gas mileage sounds about right to me, I get like 270 with about 75% stop-n-go driving. With all highway though it jumps to well over 300, closing in on 400.
2006Scorpion
04-27-2012, 04:51 AM
My car must be a freak of nature, all highway miles crusing at 75-80 I got 627 miles on a full tank, check all the things stated above maybe try getting a mild tune to help boost MPG's too.
evanferl
04-27-2012, 05:26 AM
My car must be a freak of nature, all highway miles crusing at 75-80 I got 627 miles on a full tank, check all the things stated above maybe try getting a mild tune to help boost MPG's too.
I normally get exactly 400 miles per tank, that is half highway, half city. I've gone 580 ALL highway.
Charles.waite
04-27-2012, 09:19 AM
Your gas mileage sounds about right to me, I get like 270 with about 75% stop-n-go driving. With all highway though it jumps to well over 300, closing in on 400.
No that's the thing it's not normal. I got better mpg in my old g37 and my 1.8t gets 50% better mileage on the same commute. So it's not normal.
I'm road tripping out to Montana (10hr drive each way averaging 80mph) and i'd love to get this licked. Anyone have any suggestions or solutions they've found? I know bad mpg can literally be a million things but I'm looking for "My mpgs sucked and I cleaned/fixed this and now it's better" sorts of experiences.
Don't tell me I have to do my own investigatory work!![wrench]
CorneliusRox
04-27-2012, 09:26 AM
No that's the thing it's not normal. I got better mpg in my old g37 and my 1.8t gets 50% better mileage on the same commute. So it's not normal.
I'm road tripping out to Montana (10hr drive each way averaging 80mph) and i'd love to get this licked. Anyone have any suggestions or solutions they've found? I know bad mpg can literally be a million things but I'm looking for "My mpgs sucked and I cleaned/fixed this and now it's better" sorts of experiences.
Don't tell me I have to do my own investigatory work!![wrench]
No codes being thrown?
weird that it runs great, makes this tough.
It could also be the shitty enthanol they put in our gas? I noticed the drop in MPG years ago when they started adding a min 10% ethanol mixture. Combine that with Cali's 91 max octane grade and it just robs our engines peak performance.
This is about as dense as ignorant statements can get.
lol tell him Sprode.
papadelogan
04-27-2012, 09:30 AM
Have you checked all the items listed in post # 11?
MAF clean element.
Tire pressure (as stated).
Oil viscosity
Carbon build up
Air filter
Plugs
Fuel Grade
Fuel Filter
Dirty injectors
Once you've checked all of them, then it's time to hunt for issues:
PCV - mine got ditched and I went with a BSH PCV Revamp kit - $100 and never worry about it again
vacuum lines - may be pinched or have a tear/hole - I haven't checked mine
DV, N80, N75 - do you know they are working right and are you on the latest revision?
Get all your maintenance up & current - these cars can't be skimped on, and think of it this way - instead of dumping your money out the tailpipe with crappy MPGs, put those $$$ in to getting your car running properly - you'll save money in the long run. getting 420 miles off a tank means you cut your fuel bill by 1/3, and how quickly will that add up?
Charles.waite
04-27-2012, 09:31 AM
No codes. I'm going to mess around today and tonight and log some stuff, fuel trims, MAF, etc and see if anything jumps out at me there was a bit of oil in the tb hose when I swapped my t-stat out but nothing crazy. Seemed fairly minor to me and I know some bypass is normal.
CorneliusRox
04-27-2012, 09:41 AM
No codes. I'm going to mess around today and tonight and log some stuff, fuel trims, MAF, etc and see if anything jumps out at me there was a bit of oil in the tb hose when I swapped my t-stat out but nothing crazy. Seemed fairly minor to me and I know some bypass is normal.
I mean, it is always good to drain the oil from your drivers side intercooler.
check your AFR too
Charles.waite
04-27-2012, 10:19 AM
I mean, it is always good to drain the oil from your drivers side intercooler.
check your AFR too
Checked my fuel trims, granted my coolant temp was only 73C (short commute, haha) but they were at -3.5% idle adaptation and +6.5% for the other value. Sorry can't remember what it was called. Not sure that means anything. I'll try and get some more data today during lunch.
MAF said 2.5g/s at idle in park. Engine load was around 18% also which I believe is normal, but not positive. Its a Tiptronic BTW.