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O/R X Pipe causing bad gas mileage

  • Thread starter Thread starter tylerdred
  • Start date Start date Nov 22, 2004
T

tylerdred

Founding Member
Sep 26, 2001
75
0
6
Chicago, IL
Nov 22, 2004
#1
  • Nov 22, 2004
  • #1
I just installed a Borla Stinger catback and a mustangtuning O/R X pipe. I put on a set of used MIL eliminators. I get no check engine light. BUT I am getting horrible gas mileage. I just got 100 miles out of 3/4 of a tank!! I think the car might be running too rich. In park, the car will sometimes die at idle. What do you guys think??? What is the explanation???
 
T

TrevX

New Member
Oct 31, 2004
76
0
0
Texas
Nov 22, 2004
#2
  • Nov 22, 2004
  • #2
tylerdred said:
I just installed a Borla Stinger catback and a mustangtuning O/R X pipe. I put on a set of used MIL eliminators. I get no check engine light. BUT I am getting horrible gas mileage. I just got 100 miles out of 3/4 of a tank!! I think the car might be running too rich. In park, the car will sometimes die at idle. What do you guys think??? What is the explanation???
Click to expand...



An O/R X-Pipe should increase gas mileage unless you have your foot in it constantly like me...I'd be good to get 200 miles to a tank.
 

tomustang

Psychotic Member
Founding Member
Jun 8, 2000
3,434
2
78
McLean Hospital
Nov 22, 2004
#3
  • Nov 22, 2004
  • #3
tylerdred said:
I just installed a Borla Stinger catback and a mustangtuning O/R X pipe. I put on a set of used MIL eliminators. I get no check engine light. BUT I am getting horrible gas mileage. I just got 100 miles out of 3/4 of a tank!! I think the car might be running too rich. In park, the car will sometimes die at idle. What do you guys think??? What is the explanation???
Click to expand...


what kind of car do you have? (auto/stick?gt?96?03?) need some more info
 
T

tylerdred

Founding Member
Sep 26, 2001
75
0
6
Chicago, IL
Nov 22, 2004
#4
  • Nov 22, 2004
  • #4
More Info

2001 Auto Mustang GT
Borla Stinger Catback
Mustangtuning o/r x pipe
used mil eliminators
nitto 555r's

My gas mileage has gone down the crapper immediately after installing the pipe. I've gotten 100 miles out of a 3/4 tank. I am NOT being lead-footed.

I suspect something is wrong with the O2 simulators and that is causing the car to run tooo rich. Anyone with some info????
 
F

FalconGuy016

New Member
Oct 26, 2004
437
1
0
Northern VA
Nov 22, 2004
#5
  • Nov 22, 2004
  • #5
That would be what I would say, O2 sensors
 

COBRA90GT

Mustang Master
Sep 22, 2001
6,654
0
87
HOCKEYTOWN ® , MI
Nov 22, 2004
#6
  • Nov 22, 2004
  • #6
No check engine light?

Did you reset the car's computer/PCM by disconnecting the battery during your install?

It's possible that something could be wrong with your front O2 sensors, since the front Oxy sensors are the ones that affect drivability. It might not hurt to get the vehicle scanned for codes if you don't see an increase in gas mileage in the near future...

I know you've already touched on this, but after an exhaust install, it's typical for people to get worse gas mileage initially because they are very heavy on the throttle.
 

bigblackboat

New Member
Mar 1, 2004
43
0
0
Langhorne, Pa.
Nov 22, 2004
#7
  • Nov 22, 2004
  • #7
I had the same problem after installing my drgas x. I didn't have mil eliminators, so the check engine light was on and didn't think anything of it. I installed my mils and noticed the check engine light came back on. The guy that installed my x pipe damaged the driver side front o2 sensor. The car thought it was running lead so it compensated by dumping more fuel into the engine which resulted in my horrible gas mileage. Make sure your mils are on the back o2 sensors and not the fronts or replace your back o2's with the fronts to check for a damaged o2. Your car should be throwing a code, have it scanned anyway.
 
T

tylerdred

Founding Member
Sep 26, 2001
75
0
6
Chicago, IL
Nov 25, 2004
#8
  • Nov 25, 2004
  • #8
bigblackboat said:
I had the same problem after installing my drgas x. I didn't have mil eliminators, so the check engine light was on and didn't think anything of it. I installed my mils and noticed the check engine light came back on. The guy that installed my x pipe damaged the driver side front o2 sensor. The car thought it was running lead so it compensated by dumping more fuel into the engine which resulted in my horrible gas mileage. Make sure your mils are on the back o2 sensors and not the fronts or replace your back o2's with the fronts to check for a damaged o2. Your car should be throwing a code, have it scanned anyway.
Click to expand...

Could it be that the used MIL eliminators have gone bad???? Also, is it normal to have a gas smell inside the cabin after installing an o/r x pipe? I dont think this is normal at all, but I just want to check.
 

crew_dawg16

New Member
Apr 25, 2004
445
0
0
DeKalb, IL
Nov 25, 2004
#9
  • Nov 25, 2004
  • #9
the gas smell is normal, as for your gas mileage, try resetting your computer
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Nov 25, 2004
#10
  • Nov 25, 2004
  • #10
teh rear O2s have no effect on rich or lean conditions. their sole purpose is to moniter catalytic converter efficiency.
 

MyEarsHurt

New Member
May 21, 2004
918
0
0
Nov 25, 2004
#11
  • Nov 25, 2004
  • #11
Thats odd, my gas mileage went up a little when I got mine....well after the first week that is. Cause the whole first week my gas pedal was touching the floor at every possibility just to hear the sound.
 
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