how-to: control closed loop AFR with your wideband O2 system
The turning off the "allow closed loop" setting does go off the fuel map all the time, but it won't use the fuel trims to target the value. This patch will use the fuel trims to help hit your target. This keeps you from having to tune those low load/low rpm values that can sometimes be a pain to get exact. The fuel trims will help you get the best fuel mileage and performance by always trying to hit the values in the map.
Which Bosc wideband o2 sensor is recommended ? Is it enough to buy only the wbo2 sensor to wire it to the ecu ?
If the sensor goes bad your trims will go way out of line. These sensors, when they fail, will read out a lean voltage (normally) and the car will enrich until the fuel trim maxes out. You will see lots of black smoke from all the extra rich condition and your gas tank will empty fast!
With the stock 02 sensor you will get a check engine light, with WB02, you will not. However, hopefully you have your WB02 output displayed on a gauge or screen and you will notice that it is failing and replace it.
When it is very cold, the sensor will take more time to warm up. Just keep the car in open loop longer using settings in your rom. If it is very cold, you might have issues with some sensors.
I just did some more driving and the mod works well. If your injector scaling or latency are not dialed in, you will notice it right away. The closed loop tends to sweep more in the direction your un-tuned in. That is, if you trims where negative before applying the mod, your going to swing more to the rich side. If you trims were lean before hand, your going to swing a bit more to the lean side. This actually helped me dial in my tune at part throttle a little better.
Only time will tell if it will save me some fuel! Results later this week!
With the stock 02 sensor you will get a check engine light, with WB02, you will not. However, hopefully you have your WB02 output displayed on a gauge or screen and you will notice that it is failing and replace it.
When it is very cold, the sensor will take more time to warm up. Just keep the car in open loop longer using settings in your rom. If it is very cold, you might have issues with some sensors.
I just did some more driving and the mod works well. If your injector scaling or latency are not dialed in, you will notice it right away. The closed loop tends to sweep more in the direction your un-tuned in. That is, if you trims where negative before applying the mod, your going to swing more to the rich side. If you trims were lean before hand, your going to swing a bit more to the lean side. This actually helped me dial in my tune at part throttle a little better.
Only time will tell if it will save me some fuel! Results later this week!
I have implemented the 9653 port and it seems to work well. The 'sluggish' response of the system is indeed noticeable, but my WB02 is located in the stock rear 02 location, so this about what I expected.
I have not made any adjustments to the fuel map, so I will report back if I have success leaning out my cruise cells and 'saving' some fuel.
3gTurbo: the front 02 should report .8 volts, that is what looks normal to me. I have my WB02 setup in the rear 02 as per the instructions found in other threads (I believe post 1 from mrfred actually cites them).
I am running this on my 2G Eclipse, I'm not sure what your doing wrong but heres what I did:
-Reset ECU
-modified my XML with logics code
-Load up my V7 9653 rom with ecuflash 1.42
-copied all the required code from logic's rom he posted
-Set warmup AFR to 14.3, enabled the patch, and double checked that the MUT table was correct.
-loaded rom into ecu and started! no problems.
I would assume it is an issue with your calculations or you have incorrectly applied the patch. everything works for me, just a bit sluggish, BUT I do like it!
Great job to mrfred for making the patch, everyone appreciates your time and effort! A big thanks to Logic for the port!


I have not made any adjustments to the fuel map, so I will report back if I have success leaning out my cruise cells and 'saving' some fuel.
3gTurbo: the front 02 should report .8 volts, that is what looks normal to me. I have my WB02 setup in the rear 02 as per the instructions found in other threads (I believe post 1 from mrfred actually cites them).
I am running this on my 2G Eclipse, I'm not sure what your doing wrong but heres what I did:
-Reset ECU
-modified my XML with logics code
-Load up my V7 9653 rom with ecuflash 1.42
-copied all the required code from logic's rom he posted
-Set warmup AFR to 14.3, enabled the patch, and double checked that the MUT table was correct.
-loaded rom into ecu and started! no problems.
I would assume it is an issue with your calculations or you have incorrectly applied the patch. everything works for me, just a bit sluggish, BUT I do like it!
Great job to mrfred for making the patch, everyone appreciates your time and effort! A big thanks to Logic for the port!



I did have the wideband wired to the front o2 so i rewired it to the rear o2 sensor pin. I logged it with my 0008 rom and it is logging the wideband as the rear o2. But when i swap to the 9653 rom it doesnt log, the front o2 and rear o2 just stay the same.
Logic or MrFredd is there anyway you can change the addresses so i can use the patch on a 9417 rom? PLEASE!!!!!!
Logic or MrFredd is there anyway you can change the addresses so i can use the patch on a 9417 rom? PLEASE!!!!!!
When using the 9653 rom, have you properly setup your MUT table to read the values correctly? Have you setup evoscan correctly? Chances are if you can't get it to work with 9653, your not going to have much luck with another rom. It works and it is very easy.
First things first: Forget the patch. go back to a normal 9653 rom (V7) and get the WB02 working correctly. Follow the threads about this and get evoscan logging your WB02, while the car is running off the front narrow band.
It really sounds like your having issues trying to mod two things at once. Once you get the WB02 logging correctly with 9653, applying the patch is a 5 minuet process, heck not even that long.
and...
Yes you have to enable the patch: see the following pic: the first box to the left under the MUT has a one to enable closed loop WB logging.
First things first: Forget the patch. go back to a normal 9653 rom (V7) and get the WB02 working correctly. Follow the threads about this and get evoscan logging your WB02, while the car is running off the front narrow band.
It really sounds like your having issues trying to mod two things at once. Once you get the WB02 logging correctly with 9653, applying the patch is a 5 minuet process, heck not even that long.
and...
Yes you have to enable the patch: see the following pic: the first box to the left under the MUT has a one to enable closed loop WB logging.
3gEclipseTurbo: see acid's post. It sounds to me like you don't have logging for your wideband O2 set up correctly for 9653. I'm afraid I don't really have a whole lot of time to do another port of this, so someone else would have to take that on if they really wanted it.
VGergo: You need a real wideband O2 kit, such as an LC-1, ZT-2, or UEGO. The controller does considerably more than just put out an analog signal: it handles sensor warm-up and power regulation, calibration, and produces a clean, linear output.
VGergo: You need a real wideband O2 kit, such as an LC-1, ZT-2, or UEGO. The controller does considerably more than just put out an analog signal: it handles sensor warm-up and power regulation, calibration, and produces a clean, linear output.
I did all that....

When using the 9653 rom, have you properly setup your MUT table to read the values correctly? Have you setup evoscan correctly? Chances are if you can't get it to work with 9653, your not going to have much luck with another rom. It works and it is very easy.
First things first: Forget the patch. go back to a normal 9653 rom (V7) and get the WB02 working correctly. Follow the threads about this and get evoscan logging your WB02, while the car is running off the front narrow band.
It really sounds like your having issues trying to mod two things at once. Once you get the WB02 logging correctly with 9653, applying the patch is a 5 minuet process, heck not even that long.
and...
Yes you have to enable the patch: see the following pic: the first box to the left under the MUT has a one to enable closed loop WB logging.

First things first: Forget the patch. go back to a normal 9653 rom (V7) and get the WB02 working correctly. Follow the threads about this and get evoscan logging your WB02, while the car is running off the front narrow band.
It really sounds like your having issues trying to mod two things at once. Once you get the WB02 logging correctly with 9653, applying the patch is a 5 minuet process, heck not even that long.
and...
Yes you have to enable the patch: see the following pic: the first box to the left under the MUT has a one to enable closed loop WB logging.

Coud we use the LC-1 Wideband Controller to control the closed loop afr ? No random reseting like travman said at the begining of the topic ? I would place the sensor @ bend of the dp.
Anyone here ?? Which wideband shoud I buy for the controling the closed loop AFR a simple cheap LC1 is engoug or go with AEM or Zeitronix only ?! I would buy a reliable solution to control my cruise afr.
If you have a trouble free LC-1 then it will work great.......
I see, thank you just the ZT2 has many other function what i dont need but if it is the only one which can work everyday.. Maybe someone with AEM Uego ?
Powerdex AFX
I have been using the Powerdex AFX wideband to log A/F Through the rear O2 for a few months now. I would like to use it with this patch as well. Can any body tell me what adjustments I would have to make to use this wideband?




