02 sensor question? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

BottleFEED · 03-16-2014, 05:27 PM

I've seen do's an don'ts on running front 02 sensors and I've seen guys not run them all together. Is it safe to ditch the fronts or not. What will happen if I don't run them?

B-_-RAD · 03-16-2014, 06:12 PM

No, do not run without front o2's. You'll be stuck in open loop and just dumping fuel since the computer can't tell what's going on. You can ditch the rears all you want, but not fronts.

BottleFEED · 03-16-2014, 06:54 PM

So I will be running really rich ? That's is the only bad thing ?

axis · 03-16-2014, 07:14 PM

The front O2 sensors are what gives the PCM the feedback on how the car is running. NO ONE runs without those. The REARS are the ones that do nothing for the tune. They are only there to tell you if the cats are working.

BottleFEED · 03-16-2014, 07:31 PM

I've seen a few camaros an stands run with out fronts just wondering what the cons are to them. I know what they do but wondering how the hell they are doing it.. What happens if you don't ? Your in open loop but what's the issue with it ?

axis · 03-16-2014, 07:43 PM

Quote:

Originally Posted by BottleFEED

I've seen a few camaros an stands run with out fronts just wondering what the cons are to them. I know what they do but wondering how the hell they are doing it.. What happens if you don't ? Your in open loop but what's the issue with it ?

I've yet to see a modern ECU car run without an O2 sensor. Something has to give the ECU feedback on how well the car is being fueled. Carb'd cars don't O2 sensors but they don't have ECU's either.

There are issues on both sides of the fence. If you're too rich, you'll bog all the time from fuel dump. If you're too lean, you can blow your engine up. Is there a point to your question? Are you wanting to run your car without O2 sensors?

BLACK10 · 03-16-2014, 08:09 PM

Quote:

Originally Posted by axis

The front O2 sensors are what gives the PCM the feedback on how the car is running. NO ONE runs without those. The REARS are the ones that do nothing for the tune. They are only there to tell you if the cats are working.

this is not 100%.correct. It is possible to not have to use front O2's.

axis · 03-16-2014, 08:16 PM

Quote:

Originally Posted by BLACK10

this is not 100%.correct. It is possible to not have to use front O2's.

What gives feedback to the ECU?

BLACK10 · 03-16-2014, 08:24 PM

Quote:

Originally Posted by axis

What gives feedback to the ECU?

Im not a tuner so I dont want to pretend that I am one, but it can be tuned in speed density via the MAP sensor. You do use a wideband sensor to create a mapping for the ecm. Once all the air and fueling is defined the front o2's can be removed or left in but they are only there to monitor.We tune quite a few cars(mainly high hp sc'ed) in speed density.

BottleFEED · 03-16-2014, 08:28 PM

I am waiting on my 02 extensions and wondering about it since I've seen people run with out. I guess my question was answer on how they did it.

BLACK10 · 03-16-2014, 08:30 PM

Quote:

Originally Posted by BottleFEED

I am waiting on my 02 extensions and wondering about it since I've seen people run with out. I guess my question was answer on how they did it.

If your car is not tuned for it, DO NOT run the car without front o2 sensors!

BottleFEED · 03-16-2014, 08:38 PM

What would happen ?

axis · 03-16-2014, 08:48 PM

Quote:

Originally Posted by BLACK10

Im not a tuner so I dont want to pretend that I am one, but it can be tuned in speed density via the MAP sensor. You do use a wideband sensor to create a mapping for the ecm. Once all the air and fueling is defined the front o2's can be removed or left in but they are only there to monitor.We tune quite a few cars(mainly high hp sc'ed) in speed density.

My old Talon turbo was speed density via TEC III, but I thought it used the O2 sensor to aid in fueling. I know it used the MAP and IAT sensors. So basically once you're reaching the limits of the OEM MAF, you need to switch to SD? I can't see our blade MAF being that restrictive to make SD something that would make more HP from switching.

Sorry OP, I guess I wasn't 100% correct. There are special considerations and a good bit of tuning required to run SD reliably. The car does have the abilty to run SD within the OEM pcm too and will switch to SD if there's a MAF issue.

ZO6 Bryan · 03-16-2014, 09:13 PM

The cars can be tuned to run in open loop. Then you don't need the feedback from the O2 sensors. With some big cam cars it might be beneficial but for most streetcars you're going to want to keep the O2's. A lot of the Holden cars in Australia were all running open loop until a few years ago. They would come that way from the factory.

03-16-2014, 05:27 PM	#1
BottleFEED Drives: 2010 2SS/RS M6 Join Date: Dec 2013 Location: Home state: Minnesota STATIONED - Hawaii Posts: 308	02 sensor question? I've seen do's an don'ts on running front 02 sensors and I've seen guys not run them all together. Is it safe to ditch the fronts or not. What will happen if I don't run them? __________________

03-16-2014, 06:54 PM	#3
BottleFEED Drives: 2010 2SS/RS M6 Join Date: Dec 2013 Location: Home state: Minnesota STATIONED - Hawaii Posts: 308	So I will be running really rich ? That's is the only bad thing ? __________________

03-16-2014, 07:14 PM	#4
axis Search Ninja Drives: 2010 Black 2SS/RS A6 Join Date: Oct 2009 Location: Central Ark Posts: 7,183	The front O2 sensors are what gives the PCM the feedback on how the car is running. NO ONE runs without those. The REARS are the ones that do nothing for the tune. They are only there to tell you if the cats are working. __________________ 2010 Black 2SS/RS A6 Halltech CF 102 fed GPI modded intake manifold Bo (knows) White ported TB Kooks LT's/ Dynomax VT Pfadted (springs/sways) Dyno tuned by Rhino and GPI I once parallel parked a train.

03-16-2014, 07:31 PM	#5
BottleFEED Drives: 2010 2SS/RS M6 Join Date: Dec 2013 Location: Home state: Minnesota STATIONED - Hawaii Posts: 308	I've seen a few camaros an stands run with out fronts just wondering what the cons are to them. I know what they do but wondering how the hell they are doing it.. What happens if you don't ? Your in open loop but what's the issue with it ? __________________

03-16-2014, 08:28 PM	#10
BottleFEED Drives: 2010 2SS/RS M6 Join Date: Dec 2013 Location: Home state: Minnesota STATIONED - Hawaii Posts: 308	I am waiting on my 02 extensions and wondering about it since I've seen people run with out. I guess my question was answer on how they did it. __________________

03-16-2014, 06:12 PM	#2
B-_-RAD Banned Drives: ... Join Date: Dec 2013 Location: ... Posts: 398	No, do not run without front o2's. You'll be stuck in open loop and just dumping fuel since the computer can't tell what's going on. You can ditch the rears all you want, but not fronts.

03-16-2014, 08:38 PM	#12
BottleFEED Drives: 2010 2SS/RS M6 Join Date: Dec 2013 Location: Home state: Minnesota STATIONED - Hawaii Posts: 308	What would happen ? __________________

03-16-2014, 09:13 PM	#14
ZO6 Bryan Drives: 02 Z06, 95 Trans Am, 2012 ZL1 Join Date: Mar 2012 Location: Southeast Posts: 1,838 View My Garage	The cars can be tuned to run in open loop. Then you don't need the feedback from the O2 sensors. With some big cam cars it might be beneficial but for most streetcars you're going to want to keep the O2's. A lot of the Holden cars in Australia were all running open loop until a few years ago. They would come that way from the factory. __________________ Bryan 2018 ZL1 M6