• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 V6 Mustang Tech

Running both lean and rich with O2 heat codes

  • Thread starter Thread starter Danceswithfire5
  • Start date Start date Aug 30, 2026
D

Danceswithfire5

New Member
Aug 30, 2026
1
0
1
Florida
Aug 30, 2026
#1
  • Aug 30, 2026
  • #1
Just bought my little ‘97 and she’s craving car candy. Previous owners replaced the MAF, TPS, and idle control sensors with Amazon parts (so only so much faith in those). They also replaced with oreillys parts the fuel injectors, spark plugs and wires, control arms, rack and pinion, shocks, sway bar, ball joints, hubs, fuel pump, front brakes (but not the pads), and distributor. I believe they also replaced or repaired some portion of the intake manifold and gaskets beneath it based off photos I was shown prior to purchase. It also has a PCV valve and grommet that I purchased from advanced that they installed for me prior to purchase. She drove great for about two days and then stalled at a red light. Little shudder and then just cut out with the battery light popping on. She started right back up after and then momentarily acted like she wasn’t getting gas about 5 min later.
Currently has the following codes:
P0155
P0135
P1121
P0175
P0174
Best troubleshooting methods? I bought a can of carb cleaner to look for a leak but I read that can cause fires and I’d rather not do that. Mostly work on my own cars but also open to coughing up mechanic money.
 
A

apple99Mustangdude

Member
Feb 11, 2018
62
9
18
Sep 5, 2026
#2
  • Sep 5, 2026
  • #2
Danceswithfire5 said:
Just bought my little ‘97 and she’s craving car candy. Previous owners replaced the MAF, TPS, and idle control sensors with Amazon parts (so only so much faith in those). They also replaced with oreillys parts the fuel injectors, spark plugs and wires, control arms, rack and pinion, shocks, sway bar, ball joints, hubs, fuel pump, front brakes (but not the pads), and distributor. I believe they also replaced or repaired some portion of the intake manifold and gaskets beneath it based off photos I was shown prior to purchase. It also has a PCV valve and grommet that I purchased from advanced that they installed for me prior to purchase. She drove great for about two days and then stalled at a red light. Little shudder and then just cut out with the battery light popping on. She started right back up after and then momentarily acted like she wasn’t getting gas about 5 min later.
Currently has the following codes:
P0155
P0135
P1121
P0175
P0174
Best troubleshooting methods? I bought a can of carb cleaner to look for a leak but I read that can cause fires and I’d rather not do that. Mostly work on my own cars but also open to coughing up mechanic money.
Click to expand...
Danceswithfire5 said:
Just bought my little ‘97 and she’s craving car candy. Previous owners replaced the MAF, TPS, and idle control sensors with Amazon parts (so only so much faith in those). They also replaced with oreillys parts the fuel injectors, spark plugs and wires, control arms, rack and pinion, shocks, sway bar, ball joints, hubs, fuel pump, front brakes (but not the pads), and distributor. I believe they also replaced or repaired some portion of the intake manifold and gaskets beneath it based off photos I was shown prior to purchase. It also has a PCV valve and grommet that I purchased from advanced that they installed for me prior to purchase. She drove great for about two days and then stalled at a red light. Little shudder and then just cut out with the battery light popping on. She started right back up after and then momentarily acted like she wasn’t getting gas about 5 min later.
Currently has the following codes:
P0155
P0135
P1121
P0175
P0174
Best troubleshooting methods? I bought a can of carb cleaner to look for a leak but I read that can cause fires and I’d rather not do that. Mostly work on my own cars but also open to coughing up mechanic money.
Click to expand...
I am just an average DIY'er, not an expert, but I watch tons of Scotty Kilmer video's (long time mechanic as his dad was before him, Car Wizard, etc- I have read that MAF sensors are one of the parts that you need to go OEM on, double check that online - that often aftermarket ones do not work properly, even when new. I have been trying to find out where to buy really good quality parts on my 99 Mustang six, by beloved daily driver. I would much rather pay perhaps to have a starter or alternator rebuilt as in the old days, then to have the original one last forever, and the have the next ones go out every few months or a year or so - had bad problems with NAPA decades ago, 83 Plymouth Reliant, with 2.2 - original starter lasted over 100K, NAPA-crappa lasted a few months. Mechanic would say - well, it is covered under warranty - but I had to pay for labor, AND you never knew where you would break down - it could be in a deadly situation, like 115 degree heat - or in my parents case, picking up the dog from surgery, on a hot day, to take her home and take care of her -
 
You must log in or register to reply here.

Similar threads

Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
J
Progress Thread Family member 1989 GT- Backstory and updates
  • JRC99
  • Apr 19, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
15
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 26, 2025
JRC99
J
J
89 2.3 LX running rich, hesitation on acceleration, high and hanging idle Help!
  • jpstucky
  • Jun 13, 2023
  • 2.3L (N/A & Turbo) Tech
Replies
4
Views
3K
2.3L (N/A & Turbo) Tech Jun 15, 2023
jpstucky
J
Fuel Running lean but no o2 sensor codes?
  • Creomod
  • May 22, 2021
  • Fox 5.0 Mustang Tech
Replies
11
Views
5K
Fox 5.0 Mustang Tech Sep 4, 2021
manicmechanic007
3
my '00 3.8L has a couple issues, need insight.
  • 305newedge
  • Jul 5, 2021
  • SN95 V6 Mustang Tech
Replies
4
Views
1K
SN95 V6 Mustang Tech Jul 27, 2021
Toofastt
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 V6 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?