O2 switching question. Over what time frame
#1
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O2 switching question. Over what time frame
should you expect healthy O2's to switch above and below 450 mv.
Should i be like 4 switches per second or somethign like that....
Should i be like 4 switches per second or somethign like that....
#2
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I see my stockers swinging 1-2 per second but also
see this varying a lot with engine RPM. The faster it
spins the faster the cross-counts. At idle it can be
one crossing every 2-3 seconds and at highway cruise
5-7 per second.
I think if you mess around that time constant / linear
control stuff you can change the cross-count behavior
a lot (I haven't touched it).
I see guys with headers having no action at all (O2 low)
and then a single jump-up, followed by another lull - not
an even switch - reswitch train. This asymmetry I think
is a good indicator of a thermal problem. On mine even
when the cross-counts slow down the switching waveform
retains a general symmetry.
see this varying a lot with engine RPM. The faster it
spins the faster the cross-counts. At idle it can be
one crossing every 2-3 seconds and at highway cruise
5-7 per second.
I think if you mess around that time constant / linear
control stuff you can change the cross-count behavior
a lot (I haven't touched it).
I see guys with headers having no action at all (O2 low)
and then a single jump-up, followed by another lull - not
an even switch - reswitch train. This asymmetry I think
is a good indicator of a thermal problem. On mine even
when the cross-counts slow down the switching waveform
retains a general symmetry.
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Originally Posted by HumpinSS
should you expect healthy O2's to switch above and below 450 mv.
Should i be like 4 switches per second or somethign like that....
Should i be like 4 switches per second or somethign like that....
At idle, you want to see them switch like a since waveform around once every second. The faster the better, but you dont want squaring off at max. amplitude either. In motion, you will see them pick up speed and start looking like a seismic event. When you go out of range they will rail either rich at high amplitude or lean at low amplitude. In PE mode you expect to see them railing. Their mv reading at WOT is also a rough indicator of your AFR. For example, at WOT I command 12.7AFR and they read 920mv. Their gradual rise over a WOT run is directly proportional to my PE curve.
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There are a few options available to you. Any one or all of the below will help:
1. Heatwrap or ceraminc coated headers
2. replace with higher temp. sensors
3. Move sensors forward
4. Add O2 Gain by increasing the Base Airflow Tables in Closed Loop
1. Heatwrap or ceraminc coated headers
2. replace with higher temp. sensors
3. Move sensors forward
4. Add O2 Gain by increasing the Base Airflow Tables in Closed Loop
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Originally Posted by luv2spd
How can I get my 02s to switch faster? At idle mine basically don't switch at all.
Or, you have a dying/cool O2 meter. Replace with corvette rears (think I got the Bosch ones)
The o2s should be bouncing around in idle closed loop.
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Originally Posted by MNR-0
There are a few options available to you. Any one or all of the below will help:
1. Heatwrap or ceraminc coated headers
2. replace with higher temp. sensors
3. Move sensors forward
4. Add O2 Gain by increasing the Base Airflow Tables in Closed Loop
1. Heatwrap or ceraminc coated headers
2. replace with higher temp. sensors
3. Move sensors forward
4. Add O2 Gain by increasing the Base Airflow Tables in Closed Loop
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Originally Posted by luv2spd
Could I use the values off of your file on horist's site to accomplish this? I am cammed also so I don't know what effect this will have with airflow modes or if I could just use the values that you used.
Check this out. Plus in these Airflow Modes and use the Closed Loop Proportional Base Airflow values to raise your O2 sensor gain.
You should find your LTFTs settle in ALL environmental conditions as a bonus.
https://ls1tech.com/forums/showpost....7&postcount=65
https://ls1tech.com/forums/showpost....7&postcount=74
#11
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Originally Posted by SSpeedracer
I played around with this a few months ago. Make small changes each time and log the results. HPtuners - Fuel Control - Open/Closed Loop - closed loop prop
Or, you have a dying/cool O2 meter. Replace with corvette rears (think I got the Bosch ones)
The o2s should be bouncing around in idle closed loop.
Or, you have a dying/cool O2 meter. Replace with corvette rears (think I got the Bosch ones)
The o2s should be bouncing around in idle closed loop.
I have changed the MAP boundaries and tried to adjust the 02 switching values lower to compensate, but I still see too much fuel at idle.
Thanks for any help.
#12
Originally Posted by Closer_2001
Tell me more - after my G5X3 Cam was installed - the 02s falsely report a lean condition and push LTFT SKY High!! I assumed this was due to cam overlap. If I keep adjusting the base VE to compensate - I eventually smell like I'm towing a trailer of rotten eggs.
I have changed the MAP boundaries and tried to adjust the 02 switching values lower to compensate, but I still see too much fuel at idle.
Thanks for any help.
I have changed the MAP boundaries and tried to adjust the 02 switching values lower to compensate, but I still see too much fuel at idle.
Thanks for any help.