• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-

slight situation

  • Thread starter Thread starter disturbdgt
  • Start date Start date May 1, 2009

disturbdgt

Member
Apr 8, 2007
90
0
7
suffolk, va
May 1, 2009
#1
  • May 1, 2009
  • #1
ok so i think i have a slight problem. After installing my lt headers my gas mileage has gone down, way down. Before i installed the lts i was getting like 18 mpg with all mods listed in sig except for lts. And with everything else besides 4:10s and lts i was averaging 20-21 mpg. All this is averaged between city and highway driving mixed. ex: miles per tank divided by gallons of gas put in tank. So do i need to get a tune for the lts or what. because right now i am getting like 15-16 mpg per tank.
 

Winters98GT

Whoop...whoop-whoop-whoop-whoop...GANGNAM STYLE!!!
Founding Member
Nov 29, 1999
5,520
1,291
224
H Town
May 1, 2009
#2
  • May 1, 2009
  • #2
Yep, I would get the car tuned. I'm not up to date on the sct software, but after longtubes, I would recommend a dyno tune, or at least a good shop with a wideband. Something is not right if you are loosing that much on your milage.
 

myponyrocks

I have more billet on the Stang than most women ha
Apr 18, 2004
1,219
0
37
May 2, 2009
#3
  • May 2, 2009
  • #3
LTs and some brands of shorties require a tune, Modular Powerhouse did mine and it was dead on through the mail
 

bhuff30

Founding Member
Dec 11, 2001
6,037
35
129
Olathe KS
May 2, 2009
#4
  • May 2, 2009
  • #4
The O2 sensor is located much further away from the engine with long tubes. It may not be getting hot fast enough or staying hot enough to stay in closed loop. A dyno tune should give you an idea what's going on, but you may need to replace the O2 sensors.
 

disturbdgt

Member
Apr 8, 2007
90
0
7
suffolk, va
May 2, 2009
#5
  • May 2, 2009
  • #5
so i guess a dyno tune will be my next step then.
 

LaserSVT

Got FB banned again for saying nards
Founding Member
Nov 29, 1999
9,389
3,536
233
May 2, 2009
#6
  • May 2, 2009
  • #6
disturbdgt said:
so i guess a dyno tune will be my next step then.
Click to expand...
Yes.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
May 2, 2009
#7
  • May 2, 2009
  • #7
disturbdgt said:
so i guess a dyno tune will be my next step then.
Click to expand...

I would say yes....and if you've got any other minor bolt ons planned in the near future, I would go ahead and install them before taking it to the dyno. You might as well get tuned with all of the parts in place, rather than tune it the way it is and start throwing parts into the mix again to add to the inaccuracy a second time.
 

disturbdgt

Member
Apr 8, 2007
90
0
7
suffolk, va
May 2, 2009
#8
  • May 2, 2009
  • #8
well as far as engine mods the only thing i may do now is just steeda udp's thats about it.
 

disturbdgt

Member
Apr 8, 2007
90
0
7
suffolk, va
May 2, 2009
#9
  • May 2, 2009
  • #9
well im def gonna get a tune. and i do think that my right foot is part of the problem too. but well see, cause i think i may know what it may be also. About a month ago, end of march i went and got new tires put up front. and while checking my tire pressure today i noticed that my rears are at what i normally put them at. 36psi. but my fronts were put way up at 43psi, so could this of been my problem too.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
May 2, 2009
#10
  • May 2, 2009
  • #10
disturbdgt said:
About a month ago, end of march i went and got new tires put up front. and while checking my tire pressure today i noticed that my rears are at what i normally put them at. 36psi. but my fronts were put way up at 43psi, so could this of been my problem too.
Click to expand...

If anything, increased tire pressure will help your fuel economy by decreaseing rolling resistance.
 
You must log in or register to reply here.

Similar threads

Who the hell puts the wrong spark plugs in a 3.8L?
  • snowstang
  • Mar 25, 2026
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
12
Views
371
1996 - 2004 SN95 Mustang -General/Talk- Apr 3, 2026
LILCBRA
2
Running very very rich
  • 2esoteric
  • Oct 31, 2025
  • Fox 5.0 Mustang Tech
Replies
4
Views
305
Fox 5.0 Mustang Tech Oct 31, 2025
Noobz347
B
'03 GT Fuel Pump/Pressure/Delivery Issue
  • Brodach
  • Oct 21, 2025
  • SN95 4.6L Mustang Tech
Replies
8
Views
818
SN95 4.6L Mustang Tech Oct 31, 2025
gkomo
X
Free VE Table Corrections — Drop Your MSQ and a Datalog, I'll Do the Rest
  • X-cam34
  • Apr 12, 2026
  • Digital Self-tuning Forum
Replies
8
Views
274
Digital Self-tuning Forum May 21, 2026
X-cam34
X
F
Resolved Stumble issue upon acceleration (1987 GT)
  • FoxDude87
  • Sep 16, 2024
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
54
Views
3K
Fox 5.0 Mustang Tech Dec 3, 2024
FastDriver
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?