Anyone turn all your O2's OFF
Anyone turn all your O2's OFF 
06-29-2009, 09:33 PM
#4
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Well it depends on what type of tune you are running.
If you are running closed-loop, you will need the front O2's working. They keep you running at stoich (~14.63 AFR).
If you run open loop, you do not need then. But you can easily disable them by using tuning software.
I prefer closed-loop, so I have high-flow cats and use the front O2's to trim.
Thats the short version of closed & open-loop.
..WeathermanShawn..
If you are running closed-loop, you will need the front O2's working. They keep you running at stoich (~14.63 AFR).
If you run open loop, you do not need then. But you can easily disable them by using tuning software.
I prefer closed-loop, so I have high-flow cats and use the front O2's to trim.
Thats the short version of closed & open-loop.
..WeathermanShawn..
06-30-2009, 07:14 AM
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No, you are using the tuning software using the O2 Parameter Table. (Closed-Loop Temp Enable). You simply increase the O2 enable temperature to max (~140C), and effectively 'disable' entering closed-loop.
To clarify, that is not the same as disabling them under the Engine Diagnostic section. The front O2's sensors still actually work. They will simply not display an active MIL or DTC code.
That makes it easier for those that have to comply with an OBD-II emissions check. You will not have an active DTC or MIL displayed. Also, if you ever plan on running a custom semi-closed loop program, it's an easy software change.
To the OP, it is your choice. Just giving you some other options.
Good luck..
..WeathermanShawn..
To clarify, that is not the same as disabling them under the Engine Diagnostic section. The front O2's sensors still actually work. They will simply not display an active MIL or DTC code.
That makes it easier for those that have to comply with an OBD-II emissions check. You will not have an active DTC or MIL displayed. Also, if you ever plan on running a custom semi-closed loop program, it's an easy software change.
To the OP, it is your choice. Just giving you some other options.
Good luck..
..WeathermanShawn..
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06-30-2009, 07:26 AM
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thanks for input. Reason I asked is because with front O2's on car responds funny, idles different and hangs a bit too. With O2's off I love the way car idles , rpm's drop, just performs better to me. I understand all tuners start out with shutting O2's off anyways to dial in car then flip them on at end
06-30-2009, 07:32 AM
#9
They are there to help the car correct the fueling for weather or small mechanical changes. If you drive the car regularly it's easier to just keep them, so you don't have to be tuning the car all the time.
You're problem could be in the switch points. With using headers makes the O2s less accurate and can throw off the AFR whichs may make your car run weird as opposed to open loop. You could try playing the with switching voltagesin the tune or just disable closed loop for idle.
thanks for input. Reason I asked is because with front O2's on car responds funny, idles different and hangs a bit too. With O2's off I love the way car idles , rpm's drop, just performs better to me. I understand all tuners start out with shutting O2's off anyways to dial in car then flip them on at end
Last edited by JonCR96Z; 06-30-2009 at 07:38 AM.
07-02-2009, 01:05 AM
#15
I have been running full-time open loop with MAF. I got tired of the constant 02 sensor codes and over-rich fueling due to headers. I pulled the sensors out and tuned out all the codes. Car is running great.
It is important to tune the AFR open loop table (B3605 in EFILive) and the PE to get fueling where you want it. You need a wideband to check and double check your fueling.
I've been playing with it for about a month and am going to remove the wideband from the car soon. I'll reinstall it in the fall when the weather cools to see how I'm doing. But I'm getting consistent results now.
It is important to tune the AFR open loop table (B3605 in EFILive) and the PE to get fueling where you want it. You need a wideband to check and double check your fueling.
I've been playing with it for about a month and am going to remove the wideband from the car soon. I'll reinstall it in the fall when the weather cools to see how I'm doing. But I'm getting consistent results now.
07-02-2009, 01:59 AM
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ive noticed with mine that i dont get the jerking that i get when the o2's are working. i have it slightly richer and the jerking went away. drives alot smoother. fuel milage went down 1 or 2 mpg though. with an automatic you wouldnt experience that. but with the manual its very noticable with a good size cam.
