General Maintenance & Repairs Leaks | Squeaks | Clunks | Rattles | Grinds
Sponsored by:
Sponsored by: CARiD

O2 sensors...

Thread Tools
 
Search this Thread
 
Old Jun 26, 2011 | 02:09 PM
  #1  
junkindatrunkmx6's Avatar
Thread Starter
On The Tree
iTrader: (1)
 
Joined: Aug 2007
Posts: 111
Likes: 0
From: Avondale, AZ
Default O2 sensors...

I installed Long tubes, ORY, and GMMG. I only have front O2 sensors. I keep getting different info from different people, and I don't know what's legit. Do the rear O2s give me my Long Term Fuel Trim or do they just monitor the life of the cat? I remember being told on ls1tech that it is ok to run just the fronts. The guys at work are telling me I have to buy weld-in O2 bungs, and put them in. Other guys tell me I should buy O2 dummies. Who knows what they are talking about?

Right now my STFT and LTFT are pinned at 128 on my scanner. Accordingly, my car is running rich. I have new O2 sensors in, but they aren't crosscounting, or doing much at all.

When I first installed everything it ran great. It's been down for a long long time, and I'm trying to get it running strong again.

I just got a MAP/BARO code, that could be my whole problem. I'll address that ASAP.

It's also hard to start. and I have to wait about 10 seconds for the computer to adjust my idle before I take off or my RPMS will shoot up to about 1500-2000 everytime I push the clutch in. Does anybody know what exactly the computer wants to see before it will start?

Any help would be greatly appreciated. I'm not asking for the fix, because I may have several problems. Just trying to get some good info before I dive into the thing. Thanks.
Reply
Old Jun 26, 2011 | 03:35 PM
  #2  
junkindatrunkmx6's Avatar
Thread Starter
On The Tree
iTrader: (1)
 
Joined: Aug 2007
Posts: 111
Likes: 0
From: Avondale, AZ
Default

Also, I am stuck in open loop. Coolant temp is okay. Do I need the rear O2s for CL?
Reply
Old Jun 26, 2011 | 08:00 PM
  #3  
02v8ta's Avatar
TECH Resident
iTrader: (8)
 
Joined: Jun 2008
Posts: 958
Likes: 0
From: south jersey
Default

You don't need the rear 02s... period. How ever you need to get them tuned out and get a tune in general if you just did all that exhaust work and aren't going any further.

But anyway, can you post a video of that set up!? I've been debating what catback to go with my lt's and ory. How do you like your's? Is there rasp?
Reply
Old Jun 26, 2011 | 10:11 PM
  #4  
junkindatrunkmx6's Avatar
Thread Starter
On The Tree
iTrader: (1)
 
Joined: Aug 2007
Posts: 111
Likes: 0
From: Avondale, AZ
Default

I can. tomorrow. You won't have any regrets going with the GMMG. It sounds awesome WOT. I get compliments everywhere I go...

Last edited by junkindatrunkmx6; Jun 26, 2011 at 10:17 PM.
Reply
Old Jun 27, 2011 | 09:42 AM
  #5  
wssix99's Avatar
Save the manuals!
15 Year Member
iTrader: (5)
 
Joined: Dec 2007
Posts: 12,969
Likes: 389
From: Chicago, IL
Default

Don't believe everything you read on the internet! The GM factory service manual states that the rear O2's are used in the fuel calculations. (They definitely don't have a large influence, though.) Obviously, if you tune them out, that will fool the car in to thinking they are there and happy.
Reply
Old Jun 27, 2011 | 09:25 PM
  #6  
02v8ta's Avatar
TECH Resident
iTrader: (8)
 
Joined: Jun 2008
Posts: 958
Likes: 0
From: south jersey
Default

Originally Posted by junkindatrunkmx6
I can. tomorrow. You won't have any regrets going with the GMMG. It sounds awesome WOT. I get compliments everywhere I go...
Today is tomorrow, Tomorrow is today!!!
So no rasp with that setup? How's the idle?

Originally Posted by wssix99
Don't believe everything you read on the internet! The GM factory service manual states that the rear O2's are used in the fuel calculations. (They definitely don't have a large influence, though.) Obviously, if you tune them out, that will fool the car in to thinking they are there and happy.
So IF they were messing anything up, the tune will 100% eliminate them as causing a problem. I was always under the impression though they could never effect anything to the point of actually noticing it, As far as just an exhaust swap.
Reply
Old Jun 28, 2011 | 10:28 AM
  #7  
wssix99's Avatar
Save the manuals!
15 Year Member
iTrader: (5)
 
Joined: Dec 2007
Posts: 12,969
Likes: 389
From: Chicago, IL
Default

I doubt that the missing O2 sensors are messing anything up other than giving you a code and/or reporting that your catalyst is bad. If the GM Factory manual is correct, I'd guess that they would help in fine tuning the mix so the catalytic converter will be happiest. The first set of sensors should play a (by far) dominant role in the calculations.
Reply
Old Jun 29, 2011 | 03:40 PM
  #8  
Gallstaff's Avatar
Launching!
iTrader: (1)
 
Joined: May 2006
Posts: 284
Likes: 1
From: Charlotte, NC
Default

I have the same setup as you: Longtubes, ORY, and GMMG's. I bought two o2 sims for the rear because there weren't any good tuners in my area. They took care of my check engine light and I'm getting really good mileage and power with just the front o2's. If it's going to be a pain in your ***, you can get away with throwing some sims on there and just making sure your front sensors are legit.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-1

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-2

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-3

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-4

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-5

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-6

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-7

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-8

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-9

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
Old Jun 29, 2011 | 05:27 PM
  #9  
02v8ta's Avatar
TECH Resident
iTrader: (8)
 
Joined: Jun 2008
Posts: 958
Likes: 0
From: south jersey
Default

Gallstaff do you have exhaust videos !?
Reply
Old Jun 29, 2011 | 07:44 PM
  #10  
Gallstaff's Avatar
Launching!
iTrader: (1)
 
Joined: May 2006
Posts: 284
Likes: 1
From: Charlotte, NC
Default

Originally Posted by 02v8ta
Gallstaff do you have exhaust videos !?
I could certainly get some for you tomorrow.
Reply
Old Jun 29, 2011 | 07:48 PM
  #11  
Roarin_8's Avatar
12 Second Club
20 Year Member
Photogenic
Liked
Loved
iTrader: (6)
 
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Default

Only been running front 02s, got the rear 02s tuned out 5 years ago, car still running good. Just be prepared to change the front 02s at about every 20,000 miles, at least that's what I get out of these Bosch ones. Real easy to change them out with the right 02 sensor socket tool. The driver's side electrical connector is a bit of a squeeze to get to.
Reply
Old Jun 29, 2011 | 08:30 PM
  #12  
02v8ta's Avatar
TECH Resident
iTrader: (8)
 
Joined: Jun 2008
Posts: 958
Likes: 0
From: south jersey
Default

Please do !
Reply
Old Jun 30, 2011 | 02:00 PM
  #13  
junkindatrunkmx6's Avatar
Thread Starter
On The Tree
iTrader: (1)
 
Joined: Aug 2007
Posts: 111
Likes: 0
From: Avondale, AZ
Default

Thanks for the replies. I swapped my map sensor, and my O2s are new. Anybody know why my car won't go into closed loop? Or why my O2s aren't cross counting? I could really use some help here.
Reply




All times are GMT -5. The time now is 12:53 PM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE