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

Codes/o2 Sensors/Worries

  • Thread starter Thread starter gibson89LX
  • Start date Start date Jun 24, 2008

gibson89LX

Founding Member
Jan 28, 2002
1,934
1
36
Brunswick, OH
Jun 24, 2008
#1
  • Jun 24, 2008
  • #1
OK. Car started throwing a code, so I pulled them. o2 sensor Bank 1 Sensor 2 circuit failure.
Run up to autozone and snag a replacement. I toss it in, clear the code, take it for a spin for 20 minutes and no light.
Take her to work this morning. Light.
Pull the codes again, same code. Pull out the multimeter and test the wires headed up. They check out fine. Pull the fuse. Fine.

I'm going nuts here. Any ideas?
 
B

BobHyatt

New Member
Aug 7, 2007
378
1
0
Jun 25, 2008
#2
  • Jun 25, 2008
  • #2
gibson89LX said:
OK. Car started throwing a code, so I pulled them. o2 sensor Bank 1 Sensor 2 circuit failure.
Run up to autozone and snag a replacement. I toss it in, clear the code, take it for a spin for 20 minutes and no light.
Take her to work this morning. Light.
Pull the codes again, same code. Pull out the multimeter and test the wires headed up. They check out fine. Pull the fuse. Fine.

I'm going nuts here. Any ideas?
Click to expand...

you might be losing your fuel pump. That will make it run lean no matter what the computer does, and it can assume that the O2 sensor is out of range although I more commonly see the usual lean bank 1 or whatever...

Otherwise either a bad new O2, or a wiring chafe problem somewhere.
 

gibson89LX

Founding Member
Jan 28, 2002
1,934
1
36
Brunswick, OH
Jun 25, 2008
#3
  • Jun 25, 2008
  • #3
BobHyatt said:
you might be losing your fuel pump. That will make it run lean no matter what the computer does, and it can assume that the O2 sensor is out of range although I more commonly see the usual lean bank 1 or whatever...

Otherwise either a bad new O2, or a wiring chafe problem somewhere.
Click to expand...
Doubt it's the fuel pump. That'd cause a code on the fore o2s, not the aft. Plus, it runs fine.
I hope it's not a bad new o2. They don't take those things back even if they're bad, simply because they're electronics

I'm thinking wiring, but the multimeter checked them out fine
 

gibson89LX

Founding Member
Jan 28, 2002
1,934
1
36
Brunswick, OH
Jun 26, 2008
#4
  • Jun 26, 2008
  • #4
Fixed.
Wound up being a loose connection. A pin in the harness wasn't making a good connection. I just eliminated the harness and spliced them together
 
You must log in or register to reply here.

Similar threads

A
P0036 P0056 P0137 P0157 2020 Ford Mustang GT
  • AmkoA
  • Jun 16, 2026
  • 2024+ (S650) Mustang -General/Talk
Replies
0
Views
282
2024+ (S650) Mustang -General/Talk Jun 16, 2026
AmkoA
A
0
Engine Multiple o2 sensor codes, car runs terrible
  • 02newedge
  • Jun 12, 2025
  • SN95 4.6L Mustang Tech
Replies
5
Views
627
SN95 4.6L Mustang Tech Jul 19, 2025
squeak93
Tuners come on inside
  • squeak93
  • Feb 13, 2026
  • SVT Tech Forum
Replies
1
Views
365
SVT Tech Forum Feb 20, 2026
squeak93
A
2020 Ford Mustang GT P0036, P0138, P0141 02 sensor help
  • AmkoA
  • Jul 29, 2025
  • 2015 - 2023 (S550) Mustang -General/Talk
Replies
1
Views
454
2015 - 2023 (S550) Mustang -General/Talk Aug 5, 2025
skkrtis
S
G
2006 Mustang GT o2 Sensor Wiring Issue Car Bogging/Choking
  • GCantero93
  • Sep 5, 2025
  • 2005 - 2009 Specific Tech
Replies
4
Views
1K
2005 - 2009 Specific Tech Sep 6, 2025
Noobz347
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?