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Horrible gas mileage for my 06 GXP

rguy200073

rguy200073

New member
So I just wanted to see if this is common or if there is something that I can do to improve my gas mileage.

102,000 miles, Averaging 14 mpg easy driving around town. No traffic just surface streets, Car reads 50 miles left in the tank and I am at 190 miles since fill up so if that is accurate, I will get maybe 240 out of the tank which seems very low.

I still only fill up once every 2 weeks since I live close to work and everything else, but this sitll sucks and i would love to get the 18-19 city that i am supposed to be getting.


Any help??
 


Sadly, it's a 5.3 V8.

DOD doesn't help in the city.

You could do pcv, fuel filter, new o2's, seafoam it, change fluids/new plugs, proper tire pressure, and some flow mods might help the MPG's...but they don't really do that great on gas anyways.
 
blueguy91 said:
Sadly, it's a 5.3 V8.

DOD doesn't help in the city.

You could do pcv, fuel filter, new o2's, seafoam it, change fluids/new plugs, proper tire pressure, and some flow mods might help the MPG's...but they don't really do that great on gas anyways.
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ehh...ok. Well at least it isnt something wrong with the car. I hate that DOD. I think i will have my local tuner shut it off. Thanks for your help!
 


Jteske88 said:
not gonna happen, unless your doing over 55
Click to expand...

So im just curious then....when did GM actually get the 18-19mpg city that they stated? I dont get it lol. I mean, I understand that my car has 102,000 miles on it, so I dont expect it to get that, but i was hoping for at least more than 13.7 lol.
 
They likely consider city driving to be more than a 5-10 minute drive.

I only get 14-16 mpgs right now in my GTP, I do 5-6 miles a day round trip for work.
 


Make sure you run the high octane!! I have a 00' GT stock.. When I use low octane by the end of month I have dropped from 22-24 ish all the way down to low 18's. I have a wally world credit card I use to get gas on so I save 15 cents off ea gallon... :-)

Still kind of blows my mind how much of a difference it makes...... ???
 
im running 93 octane never ran anything else. mpg never really have changed since i purchased the car. but i do like to watch the instant jump way up sometimes lol
 
blueguy91 said:
Sadly, it's a 5.3 V8.

DOD doesn't help in the city.

You could do pcv, fuel filter, new o2's, seafoam it, change fluids/new plugs, proper tire pressure, and some flow mods might help the MPG's...but they don't really do that great on gas anyways.
Click to expand...

^^^^ what he said helps. I average about 20 in the city and base traffic is a 1000 times worse than city traffic. I usually get 310 moles per tank and around 35 avg on the highway. Also when I did fuel filter I noticed difference. But that's bout all u can do

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blueguy91 said:
And you got two more cylinders.

Don't feel so bad now...dontcha ;)

Running 91+ octane though, right?
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Well I was but did go to 87. Didnt think it would make a difference since it is stock. But.....I just filled up with 91. I miss the 93 octane on the east cost. Was so surprised to see that Arizona doesnt have anything over 91 except for racing fuel.

tc300 said:
Make sure you run the high octane!! I have a 00' GT stock.. When I use low octane by the end of month I have dropped from 22-24 ish all the way down to low 18's. I have a wally world credit card I use to get gas on so I save 15 cents off ea gallon... :-)

Still kind of blows my mind how much of a difference it makes...... ???
Click to expand...

Yeah I will keep it at 91 from now on.

marines542 said:
^^^^ what he said helps. I average about 20 in the city and base traffic is a 1000 times worse than city traffic. I usually get 310 moles per tank and around 35 avg on the highway. Also when I did fuel filter I noticed difference. But that's bout all u can do

Sent from my DROID RAZR using Tapatalk 2
Click to expand...


310 per tank? DAMN! I can only hope for that kind of mileage in my wildest wet dream....
 
Well I got 298 on a take this week driving from north Carolina to Tennessee. City I usually don't do that good but that's the city

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i have to say that i am doing very well compared to you guys. i average about 30 when im cruising but ive never got below 23. all i have is the CAI and i have changed the oil to 5w-30 synthetic. maybe thats the difference? i have a straight run tho from my house to work. about every two n a half weeks ill fill up with 93 octane.
 
So for the first tank since i put the tires up to where they needed to be....went back to 91octane....and have tried to stay out of the throttle...i am currently at 180miles with 100 left to go from what the display reads. and it is sitting at 14.8 mpg average. Everything was reset at fill up. so already the display is 1mpg better than last tank just from getting the tire pressure where it needs to be and using better gas. i will do the math myself once i get gas again and see how accurate the display is.
 
Hmmm that's still a lot lower than mine says average driving in city traffic around here

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im getting about 18 but my avg is on base as well i have a 6mile trip daily but most of it is between 45-35mph and maybe 3-4lights to the house. I was getting very ****ty mileage with that damned dod and out the box tune from diablo but after i got hp tuners and turned off my dod and scaled my MAF freq for my 4' FWI and did a couple of other tweaks my mileage is great.
 
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