New TB equals bad gas mileage..help
10-11-2006, 07:24 PM
#21
Thread Starter
Join Date: Sep 2006
Location:
Posts: 42
RE: New TB equals bad gas mileage..help
i went from getting 20mpg to about 16-17mpg. is this a lot to lose or is that normal? i didnt think i would lose much at all.
ORIGINAL: Dan04COBRA
Erm... that's true.
Instead of figuring how many miles you got to a tank, you should be calculating your MPG by the amount of gas you're putting into your tank.
I'd forget the idea you lost any mileage until you calculate it more accurately.
ORIGINAL: Monch
yank the negative cable from the battery for a couple of hours. the computer will re-learn its' fuel curves
if you only had 1 tank so far where you noticed less mileage, it could be that when you last filled up you didn't get a complete fill. it happens sometimes that the pump gets switched off thinking you're full when in fact you are not.
yank the negative cable from the battery for a couple of hours. the computer will re-learn its' fuel curves
if you only had 1 tank so far where you noticed less mileage, it could be that when you last filled up you didn't get a complete fill. it happens sometimes that the pump gets switched off thinking you're full when in fact you are not.
Instead of figuring how many miles you got to a tank, you should be calculating your MPG by the amount of gas you're putting into your tank.
I'd forget the idea you lost any mileage until you calculate it more accurately.
10-11-2006, 07:28 PM
#22
3rd Gear Member
Join Date: Sep 2003
Location: United States
Posts: 606
RE: New TB equals bad gas mileage..help
did you reset the computer?
it is not normal.
is your idle messed up (hangs high) after the new tb/plenum?
every bolt on i've ever done has either made no difference in fuel economy or improved it somewhat. never a decrease. and i'm talking about regular driving after the few tanks of gas after modding.
it is not normal.
is your idle messed up (hangs high) after the new tb/plenum?
every bolt on i've ever done has either made no difference in fuel economy or improved it somewhat. never a decrease. and i'm talking about regular driving after the few tanks of gas after modding.
10-11-2006, 07:34 PM
#23
4th Gear Member
Join Date: Dec 2005
Location: Deltona, fl
Posts: 1,239
RE: New TB equals bad gas mileage..help
damn i wish i got 275 to a tank of gas. as of right now, the most i can get out of a tank of gas is 220 if im lucky. if your gonna cry about gas, get a 4 banger. just messin with ya. the more you do to your car the worse gas mileage you get. trust me. i went from 20-21 mpg driving normal. to 16.9-17.1mpg. consider yourself lucky
10-11-2006, 07:35 PM
#24
Thread Starter
Join Date: Sep 2006
Location:
Posts: 42
RE: New TB equals bad gas mileage..help
ya my idle did exactly that. i would rev it and on its way down it would stop at about 1000rpms and hang for a second or two then fall the rest of the way. but that didnt last very long at all, it seemed to work itself out, thats not happening anymore. and no i didnt reset my computer.
ORIGINAL: Monch
did you reset the computer?
it is not normal.
is your idle messed up (hangs high) after the new tb/plenum?
every bolt on i've ever done has either made no difference in fuel economy or improved it somewhat. never a decrease. and i'm talking about regular driving after the few tanks of gas after modding.
did you reset the computer?
it is not normal.
is your idle messed up (hangs high) after the new tb/plenum?
every bolt on i've ever done has either made no difference in fuel economy or improved it somewhat. never a decrease. and i'm talking about regular driving after the few tanks of gas after modding.
10-11-2006, 07:43 PM
#25
Super Moderator
Join Date: Jul 2003
Location:
Posts: 14,917
RE: New TB equals bad gas mileage..help
ORIGINAL: Derf00
Put back your old TB assembly and plenum assembly 
As you gain performance you will typically lose MPG you can't have both.
edit: you may want to try a tuner and dyno the car to optimize the computer setup. That will probably help you come out ahead of where you were to begin with.
ORIGINAL: Stangstud
So what do i need to do to even out the air and fuel mixture to make it right?
So what do i need to do to even out the air and fuel mixture to make it right?
As you gain performance you will typically lose MPG you can't have both.edit: you may want to try a tuner and dyno the car to optimize the computer setup. That will probably help you come out ahead of where you were to begin with.
Not exactly... these engines are choked and bottle necked from top to bottom. Performane modifications less than a SC & Nitrous should actually improve efficiency, the engine load will be less and hence giving the opportunity to increase gas mileage.
10-11-2006, 07:47 PM
#26
4th Gear Member
Join Date: Dec 2005
Location: Deltona, fl
Posts: 1,239
RE: New TB equals bad gas mileage..help
then please tell me y my gas mileage sucks dan?? i dont even get on it and it sucks. its no use, i mgith as well get an import. street bike that is. i will be prolly be getting one soon
10-11-2006, 08:03 PM
#27
4th Gear Member
Join Date: Jun 2006
Location: New York
Posts: 1,178
RE: New TB equals bad gas mileage..help
Go over everything 100%. Be sure everything is secure. I just found that my PCV valve was almost out but it was hard to see being under the intake pipe.
I would also see that the air filter did not become loose sinse the intake pipe must have been moved for the installation. Check to se that the intake air temperature sensor is in the intake tube where it belongs. Tried to send you a PM but it would not go through. Later, mark
I would also see that the air filter did not become loose sinse the intake pipe must have been moved for the installation. Check to se that the intake air temperature sensor is in the intake tube where it belongs. Tried to send you a PM but it would not go through. Later, mark
10-12-2006, 10:30 AM
#30
3rd Gear Member
Join Date: Feb 2005
Location:
Posts: 799
RE: New TB equals bad gas mileage..help
well i say that if you buy a V8 mustang GT, and are spending 400 dollars for 15 hp, i really don't think that you need to worry about gas mileage. you can complain all you want, but until you sell your mustang for an element or something, then i would not need worry.