• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Installed Offroad pipe last week, my gas mileage is horrible now

  • Thread starter Thread starter derek02gt
  • Start date Start date Jun 12, 2004
D

derek02gt

New Member
Dec 25, 2003
255
0
0
Jun 12, 2004
#1
  • Jun 12, 2004
  • #1
i dont know why but my gas has gone to crap..and i blame it on the offroad pipe but im not 100% sure so please correct me, i used to get like 255-275miles on a full tank..thats combined city/highway..now im only getting 200-210..a HUGE DROP in gas mileage..can anybody tell me why?i have installed my mil eliminators and there is a SES light still on..but this is frustrating..30 dollars of gas gives me 200 miles..please let me know whats going on...btw if i unplug the front 02 sensors..would that help?thanks
 
W

wht99gtconv

New Member
Dec 1, 2003
267
0
0
Jun 12, 2004
#2
  • Jun 12, 2004
  • #2
Did you disconnect the battery for about 5 minutes, if not do that and that should take care of the SES light. For the gas problem only thing I can think of is you might need to change your 02 sensors.
 

triggz

Founding Member
May 15, 2002
1,218
0
37
Gadsden, AL
Jun 12, 2004
#3
  • Jun 12, 2004
  • #3
If the SES light is still on, your MIL elims are faulty. The light should go off by itself soon after being patched.
I suggesting returning them and patch the O2 sensors yourself, its cheap and easy once the sensors are off. No cats will NOT hurt your gas mileage. It improved mine a bit. I just got 23.6mpg on a late nite 150mile trip home.

Heres a wiring diagram..you can get the parts at Radio Shack for under $5.
 
W

wht99gtconv

New Member
Dec 1, 2003
267
0
0
Jun 12, 2004
#4
  • Jun 12, 2004
  • #4
Sorry to disagree, but anytime the SES light comes on it has to be reset.
 

triggz

Founding Member
May 15, 2002
1,218
0
37
Gadsden, AL
Jun 12, 2004
#5
  • Jun 12, 2004
  • #5
We'll have to agree to disagree then. My trouble codes and SES light went away by itself after being patched within 10 miles just as suddenly as it originally came on.
 
W

wht99gtconv

New Member
Dec 1, 2003
267
0
0
Jun 12, 2004
#6
  • Jun 12, 2004
  • #6
How long was that ago
 

NV01GT

Member
Nov 20, 2001
44
0
6
Pearland, TX
Jun 13, 2004
#7
  • Jun 13, 2004
  • #7
It might be the LEAD FOOT syndrome.
 

triggz

Founding Member
May 15, 2002
1,218
0
37
Gadsden, AL
Jun 13, 2004
#8
  • Jun 13, 2004
  • #8
wht99gtconv said:
How long was that ago
Click to expand...

My patchwork? About 3 months ago...
 
D

derek02gt

New Member
Dec 25, 2003
255
0
0
Jun 13, 2004
#9
  • Jun 13, 2004
  • #9
sorry guys but I am truly a idiot, i meant "havent" instead of "have..I haven't installed my mil eliminators just yet..could that be a reason?is it possible to have bad o2's on a 2002 car?
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Jun 13, 2004
#10
  • Jun 13, 2004
  • #10
derek02gt said:
sorry guys but I am truly a idiot, i meant "havent" instead of "have..I haven't installed my mil eliminators just yet..could that be a reason?is it possible to have bad o2's on a 2002 car?
Click to expand...
That is your problem...that is what the MIL's do...fools the computer into thinking you have cats.
 
4

46gtsblown

Founding Member
Jan 9, 2002
278
0
0
Jun 13, 2004
#11
  • Jun 13, 2004
  • #11
True it fools the computer.
However, IF the MIL is triggered by not having cats or faulty REAR O2 sensors it will make ZERO difference to the running of the car.
The rear O2's are there purely to monitor the cat function.
The EEC will not pull timing or go into limp mode just for that.
Do not disconect the front O2 sensors this will screw things up big time.
Make sure that you have installed the O2 sensors correctly and they are hooked up.
Make sure you have no leaks
Reset the computer.
Clean your MAF ( I do this as a first step for any engine trouble shooting)
If is has been a while run some injector cleaner through it.

Dwayne
 

03poontanggt

New Member
Feb 23, 2004
296
0
0
fresno ca
Jun 13, 2004
#12
  • Jun 13, 2004
  • #12
How do you like the smell. I have the same problem with gas. I ran the hell out of it before the X and I run the hell out of it now. 255-275 before 190-210 now
 
You must log in or register to reply here.

Similar threads

E
Nightmare after tune install!
  • EnemyofTyranny
  • Mar 29, 2025
  • 2005 - 2014 S-197 Mustang -General/Talk-
Replies
1
Views
441
2005 - 2014 S-197 Mustang -General/Talk- Apr 12, 2025
89ripper
R
Exhaust bbk offroad x pipe install
  • ruggles
  • Feb 22, 2024
  • 1994 - 1995 Specific Tech
Replies
2
Views
901
1994 - 1995 Specific Tech Feb 26, 2024
ruggles
R
A
Fox Planning on building my foxbody and was wondering if I can get any tips or anything to watch out for!
  • Angelq1028
  • Oct 31, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2 3 4
Replies
76
Views
5K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 29, 2025
Robman8028
R
For Sale 94 Cobra 408w AOD Project For Sale
  • Labora
  • Oct 11, 2024
  • SN95 Mustangs For Sale (1994-04)
Replies
1
Views
1K
SN95 Mustangs For Sale (1994-04) Apr 7, 2025
Labora
New daily driver help needed.....not a mustang but mustang drivetrain.
  • Wayne Waldrep
  • Jun 17, 2024
  • Other Auto Tech
  • 3 4 5
Replies
80
Views
6K
Other Auto Tech Jul 28, 2024
manicmechanic007
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech
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?