O2 sensors and dynotune
#12
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I had my bike dyno tuned using TTS. It is tuned in "open loop" so the O2sensors aren't really doing anything but the ECM is still looking for information from them and if they weren't there, it would throw a code. I know this because one day my bike wasn't starting as fast as it use so I checked codes and the front O2 sensor code came up s I checked the front sensor and it was unplugged. Plugged it back in, cleared the code. Took care of the starting problem and no code ever came back
So if you reflash and remove the O2's it will set off a code
So if you reflash and remove the O2's it will set off a code
Last edited by rooti; 02-06-2013 at 09:46 PM.
#13
1. Stock sensors are narrowband, and are essentially ONLY good to achieve stoich value (14.6). NOTHING ELSE. You can make all the stuff up you want, a fact is a fact. They are incapable of auto tuning anything other than just leaning back out to 14.6.
http://tuneyourharley.com/biketech/c...band-o2-sensor
My understanding is "Narrow Band" doesn't refer specifically to the AFR the sensor is capable of seeing, but the voltage used to report it to the ECM. Narrow bands broadcast from 0-1 volts. "Wide Bands" broadcast from 0-4 volts. Because the WB sensors broadcast over a wider voltage, their readings are more accurate and thus the ECM is can tell precisely how lean or rich the mixture is. Good writeup on the differences in the two sensors:
http://forum.ih8mud.com/80-series-te...r-summary.html
2. When a fuel cell is set for ANYTHING other than 14.6, the o2 sensors are ignored. There is no way anyone is going to set the afr tables in closed or open loop at 14.6. That's what we are originally trying to get away from. Hence they would not even be evaluated by the ECM for ANY feedback.
http://tuneyourharley.com/biketech/c...p-fuel-mixture
(Also there are notes in the Power Vision software that read: "The closed loop bias table is used to adjust the closed loop AFR. Setting the value in this table to 450 mV will result in a closd loop AFR of 14.64; increasing the value will give a richer mixture and decreasing the value will give a leaner mixture.")
Thus, even using the stock O2 sensors, you can have a richer mixture than 14.6 and have that mixture checked and maintained by narrow band O2 sensors.
Just the fact that you are telling me the stock o2 sensors can be used to auto tune (in the sense that we are talking here) just tells me you have no idea what you are talking about, so I'm not going to argue any further with you.
http://www.fuelmotousa.com/site/power-vision.html
From that page:
Users now have the ability to Auto Tune right on the Power Vision display using either the factory O2 sensors or the optional Wideband Auto Tune kit.
Last edited by Robotech; 02-07-2013 at 01:07 AM.
#14
Join Date: Apr 2008
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SEPST
TTS
All the above use the factory narrow band O2 sensors. There are others.
If he makes a change and needs to retune, he will NOT need the o2 sensors. The o2 sensors are there to make the bike run as close to stoich as possible when in closed loop. Why would you dyno the bike but still keep and use the stock o2 sensors? That's like throwing money out the window.
I highly recommend the threads here;
https://www.hdforums.com/forum/elect...-injection-55/
Lots of really knowledgeable folks here.
#16
The tuners below don't actually use the o2 sensors, unless you load a canned map on there where the closed loop portion is still set for 14.6. The only reason the o2 sensors are left installed is so that codes aren't thrown. This is why you are able to remove and use o2 sensor eliminators. Also the thread is about dynoing the bike, not installing an add on with canned maps.
If you used any one of those tuners you mentioned, and did not use a canned map and instead got the bike dyno'd you would NOT need the stock o2 sensors (assuming you put in the o2 eliminators to not throw a code). The only reason to leave them in at that point is to not throw a code.
I understand the use of wideband sensors and how they are used, but in this case we are talking about the stock o2 sensors.
If you used any one of those tuners you mentioned, and did not use a canned map and instead got the bike dyno'd you would NOT need the stock o2 sensors (assuming you put in the o2 eliminators to not throw a code). The only reason to leave them in at that point is to not throw a code.
I understand the use of wideband sensors and how they are used, but in this case we are talking about the stock o2 sensors.
Power Vision
SEPST
TTS
All the above use the factory narrow band O2 sensors. There are others.
You might need to research this topic a bit more to understand how the ECM works and the tuning process.
There are systems like Thundermaxx that use wide band sensors. I don't have any experience with them but I understand they are not without their problems.
I highly recommend the threads here;
https://www.hdforums.com/forum/elect...-injection-55/
Lots of really knowledgeable folks here.
SEPST
TTS
All the above use the factory narrow band O2 sensors. There are others.
You might need to research this topic a bit more to understand how the ECM works and the tuning process.
There are systems like Thundermaxx that use wide band sensors. I don't have any experience with them but I understand they are not without their problems.
I highly recommend the threads here;
https://www.hdforums.com/forum/elect...-injection-55/
Lots of really knowledgeable folks here.
#17
As I said earlier, the best thing for him to do is ask his tuner. If you are happy with the way you understand something and how you're bike runs, that's great. Right or wrong.
#18
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Using the SEPST with Smart Tune, a map is loaded that is 14.6 in all AFR cells. The bike can be road tested or put on a dyno. Data is record and based upon the adjustments the ECM is making to achieve the 14.6 we will arrive at suggested changes to the VE tables. Once the VE tables are corrected to within 5% (I think) we can be satisfied with the VE table accuracy. Once this is done we can set the AFRs were we want them and be reasonably certain of the ability of the system to accurately achieve the desired AFRs. This is over simplified in a nut shell how the tuning process is done. One can go a step further and use something like a Twin Scan with wide Band sensors.
If you change your exhaust, breather, or other component that affects air flow you will want to repeat the process. I would recomend that the O2 sensors be left in place.
There are piggy back tuners that do little more than simulate O2 Sensor output. These are unable to change Idle, timing or in any way change any data in the ECM. With these devices the O2 sensors may be removed.
Last edited by jluvs2ride; 02-07-2013 at 10:24 AM.
#19
I would suggest you do some research and learn something about this topic as you clearly have a limited understanding.
Using the SEPST with Smart Tune, a map is loaded that is 14.6 in all AFR cells. The bike can be road tested or put on a dyno. Data is record and based upon the adjustments the ECM is making to achieve the 14.6 we will arrive at suggested changes to the VE tables. Once the VE tables are corrected to within 5% (I think) we can be satisfied with the VE table accuracy. Once this is done we can set the AFRs were we want them and be reasonably certain of the ability of the system to accurately achieve the desired AFRs. This is over simplified in a nut shell how the tuning process is done. One can go a step further and use something like a Twin Scan with wide Band sensors.
If you change your exhaust, breather, or other component that affects air flow you will want to repeat the process. I would recomend that the O2 sensors be left in place.
There are piggy back tuners that do little more than simulate O2 Sensor output. These are unable to change Idle, timing or in any way change any data in the ECM. With these devices the O2 sensors may be removed.
Using the SEPST with Smart Tune, a map is loaded that is 14.6 in all AFR cells. The bike can be road tested or put on a dyno. Data is record and based upon the adjustments the ECM is making to achieve the 14.6 we will arrive at suggested changes to the VE tables. Once the VE tables are corrected to within 5% (I think) we can be satisfied with the VE table accuracy. Once this is done we can set the AFRs were we want them and be reasonably certain of the ability of the system to accurately achieve the desired AFRs. This is over simplified in a nut shell how the tuning process is done. One can go a step further and use something like a Twin Scan with wide Band sensors.
If you change your exhaust, breather, or other component that affects air flow you will want to repeat the process. I would recomend that the O2 sensors be left in place.
There are piggy back tuners that do little more than simulate O2 Sensor output. These are unable to change Idle, timing or in any way change any data in the ECM. With these devices the O2 sensors may be removed.
To add, I don't even believe you understand what you are copying and pasting here. Perhaps it is you who lacks an understanding? Because if you did, you would make sense.
Last edited by izzyryder; 02-07-2013 at 10:37 AM.
#20
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Sorry, this is a very basic overview of how it works. No cutting and pasting. I have recommended a link to threads on EFI with postings by a lot smarter folks than me. I suggest you check it out.