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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

88 Lx 5.0 runs rich

  • Thread starter Thread starter f8tlfiveo
  • Start date Start date Dec 28, 2008

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Dec 28, 2008
#1
  • Dec 28, 2008
  • #1
i have an 88 5.0 motor stock other than bolt on parts, after i put an h pipe on the exhaust smells really rich. my brother did the same to his 93 gt and his does not smell at all really. just wondering if anyone knows if there is a way to fix this. thanks in advance
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Dec 28, 2008
#2
  • Dec 28, 2008
  • #2
When going from a catted to non-catted pipe, it's normal to smell additional exhaust "stink."

How much did your A/F ratio change after the swap (you noted running rich - are you able to see A/F trim in real time?)?

If you pull codes and all is well, I'd consider that the pipe alone made the difference. Cold weather makes the exhaust that much stinkier and for longer.

Just MHO.

Good luck.
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Dec 28, 2008
#3
  • Dec 28, 2008
  • #3
do you think it has anything to do with the car being speed density? is there anyway you can adjust the air fuel ratio, or is that controlled by the computer? how do you check the codes?
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Dec 28, 2008
#4
  • Dec 28, 2008
  • #4
http://forums.stangnet.com/771992-86-5-0-stutters-while-driving-help.html
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
Dec 29, 2008
#5
  • Dec 29, 2008
  • #5
Are the o2 sensors hooked up still
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Dec 29, 2008
#6
  • Dec 29, 2008
  • #6
yes the o2 sensors are hooked up and they are only 6 months old, i replaced them when i put the h pipe on, being that the car is a 88 it doesent have a check engine light, but if i check and there are codes being thrown will the car be running in "safe mode" which would make it run rich to be safe?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Dec 29, 2008
#7
  • Dec 29, 2008
  • #7
jeepguy00 said:
yes the o2 sensors are hooked up and they are only 6 months old, i replaced them when i put the h pipe on, being that the car is a 88 it doesent have a check engine light, but if i check and there are codes being thrown will the car be running in "safe mode" which would make it run rich to be safe?
Click to expand...

It would depend upon the code.

So you've had this H on for six months and only now notice that it stinks? If so, look for other causes or consider the ambient temps.

Good luck.
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Dec 29, 2008
#8
  • Dec 29, 2008
  • #8
no it stank the whole time , ive been busy and havent had time to research the problem. i just checked the codes and came up with 67 and 85 but the chart i was looking at doesent make much sense. so i dont know if the codes i am looking at are even whats wrong.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Dec 29, 2008
#9
  • Dec 29, 2008
  • #9
Reset the computer, drive it for a while and try running the codes again
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Dec 30, 2008
#10
  • Dec 30, 2008
  • #10
Is the Fuel tank ventillation system still intact and closed? Otherwise, that can lead to a fuel smell.....
 
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