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Error Code P0172 System Running Rich Bank 1

  • Thread starter Thread starter DAZ
  • Start date Start date Jul 8, 2003
D

DAZ

Founding Member
Jun 7, 2002
180
0
17
Endwell, NY
Jul 8, 2003
#1
  • Jul 8, 2003
  • #1
Recently pulled code P0172 System Running Rich Bank 1
Can anybody suggest diagnostics I can perform to determine cause of the error code.
 

SonicBlue02-3.8

New Member
Jun 28, 2003
112
0
0
Fairfield County, CT
Jul 9, 2003
#2
  • Jul 9, 2003
  • #2
When that code came up on my old 1990 T-bird, I remember having to replace an 02 sensor. How many miles are on your stang? They might have to be replaced. Hope that helped a little.

 

Lsredy2kstang

Look, I'm special, dammit
Nov 29, 1999
2,543
5
0
Woodstcock, Georgia
Jul 9, 2003
#3
  • Jul 9, 2003
  • #3
It is a o2 sensor problem. Which one, I have no clue. but go to autozone and they will be able to pull the codes and help you determine which one it is.

Travis.
 
D

DAZ

Founding Member
Jun 7, 2002
180
0
17
Endwell, NY
Jul 10, 2003
#4
  • Jul 10, 2003
  • #4
SonicBlue02-3.8 said:
When that code came up on my old 1990 T-bird, I remember having to replace an 02 sensor. How many miles are on your stang? They might have to be replaced. Hope that helped a little.

Click to expand...
Replaced all O2 sensors last month when I changed plugs and wires. Thought this would help the fuel consumption.... no effect.
 
M

mkonor

Founding Member
Apr 5, 2001
340
0
0
El Paso, Texas
Jul 10, 2003
#5
  • Jul 10, 2003
  • #5
DAZ said:
Replaced all O2 sensors last month when I changed plugs and wires. Thought this would help the fuel consumption.... no effect.
Click to expand...

This fault has multiple causes...faulty MAF, leaking intake, faulty fuel injectors, bad IAT, among others.

Even though you replaced the O2 sensors doesn't mean that they are properly sending the readings to the ECM. Bad wires and connections can also cause that fault.

Time to troubleshoot.

Oh yes, question, how is your gas mileage? How does the car idle? Acceleration?
 
D

DAZ

Founding Member
Jun 7, 2002
180
0
17
Endwell, NY
Jul 10, 2003
#6
  • Jul 10, 2003
  • #6
mkonor said:
This fault has multiple causes...faulty MAF, leaking intake, faulty fuel injectors, bad IAT, among others.

Even though you replaced the O2 sensors doesn't mean that they are properly sending the readings to the ECM. Bad wires and connections can also cause that fault.

Time to troubleshoot.

Oh yes, question, how is your gas mileage? How does the car idle? Acceleration?
Click to expand...
SUCKS! ROUGH & HIGH! SLUGGUSH for first two to three seconds.
 

mamastang

New Member
Apr 17, 2002
35
0
0
Dandridge,TN
Jan 3, 2004
#7
  • Jan 3, 2004
  • #7
dkhorse I need some help can you help
 
D

DanM

Founding Member
Jul 31, 2002
332
0
0
Jan 3, 2004
#8
  • Jan 3, 2004
  • #8
Bank 1 = Passenger side.

Because it's only one bank, I'd be inclined to check things like the O2 sensor wiring first, before you go looking at things like MAF that would effect both banks. The simplest explanation is that you have a bad wire somewhere from the O2 sensor (since you just replaced those) that's making intermittent contact and feeding the EEC a slightly rich signal. I'd inspect all the wiring very carefully, and if you really felt like some fun, I might swap the O2 sensors, clear the code, and see if it comes back and on which bank. If it comes back on Bank 2 this time, it's probably just the O2. If it comes back on Bank 1 again, it's either the wiring, or something worse.
 
J

Jamez

Founding Member
Mar 2, 2000
2,609
0
0
Tulsa, Ok
Jan 3, 2004
#9
  • Jan 3, 2004
  • #9
I got that for left bank too and it turned out to be a faulty MAF. Just so many things that could cause it will give you lots of guesses.
 
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