Failing Bosch Oxygen Sensors
05-09-2018, 12:07 AM
#1
Three Wheelin'
Thread Starter
Failing Bosch Oxygen Sensors
Just a heads up...
Some folks in my area have been using AEM Uego controllers with Bosch 4.2 sensors for a while. In my case, that is about a decade.
When I bought my EVO4, I decided to take advantage of the AEM analog signal output to log AFR. Works great.
We have been using leaded fuel all along and have had to change sensors from time to time as they have gotten loaded up with lead. I used to get several years use out of the Bosch 4.2 sensors that my AEM uses. And the failure mode was very obvious.
Well now things seem to have changed. Several of us have seen super short sensor lives, and readings that have not been obviously wrong.
I don 't know whether this is just a statistical anomaly, or if maybe something has changed in sensor production. And I don't know whether those using newer AEM products with 4.9 sensors are having issues.
Changing to a Ballenger Motorsports AFR500, with an NTK sensor. I am trying the production grade NTK, and my friend is trying the calibration grade NTK. Supposedly these NTKs tolerate leaded fuels much better than either of the Bosch products.
The Ballenger seems well made and well packaged. The person with whom I spoke was very knowledgable and professional.
Just FYI.
Some folks in my area have been using AEM Uego controllers with Bosch 4.2 sensors for a while. In my case, that is about a decade.
When I bought my EVO4, I decided to take advantage of the AEM analog signal output to log AFR. Works great.
We have been using leaded fuel all along and have had to change sensors from time to time as they have gotten loaded up with lead. I used to get several years use out of the Bosch 4.2 sensors that my AEM uses. And the failure mode was very obvious.
Well now things seem to have changed. Several of us have seen super short sensor lives, and readings that have not been obviously wrong.
I don 't know whether this is just a statistical anomaly, or if maybe something has changed in sensor production. And I don't know whether those using newer AEM products with 4.9 sensors are having issues.
Changing to a Ballenger Motorsports AFR500, with an NTK sensor. I am trying the production grade NTK, and my friend is trying the calibration grade NTK. Supposedly these NTKs tolerate leaded fuels much better than either of the Bosch products.
The Ballenger seems well made and well packaged. The person with whom I spoke was very knowledgable and professional.
Just FYI.
05-09-2018, 06:24 AM
#2
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James is very good and very knowledgeable.
His is one of the best aftermarket controllers. He’s done the research and is very clear what works and what doesn’t, in his experience. It’s all on his site.
Those of us using Bosch LSU 4.9’s that are genuine (and there are fakes out there, white box usually) with the LCU One do not have any issues. Have not heard of anyone using 4.2 in a long time.
I can understand why folks look for a more economical alternative. Thanks for the heads up.
His is one of the best aftermarket controllers. He’s done the research and is very clear what works and what doesn’t, in his experience. It’s all on his site.
Those of us using Bosch LSU 4.9’s that are genuine (and there are fakes out there, white box usually) with the LCU One do not have any issues. Have not heard of anyone using 4.2 in a long time.
I can understand why folks look for a more economical alternative. Thanks for the heads up.
05-09-2018, 03:29 PM
#3
Three Wheelin'
Thread Starter
Thankfully I do not rely on the AFR readings for anything critical.
My AEM set up was acquired when only the LSU 4.2 sensors were available and I saw no reason to change.
I suspect what may have changed is on the global supply chain side.
There are a lot of different sensors now, and sources are all over the map.
Even some of the Bosch sensors are apparently made by NTK.
We'll see how this works out.... not giving up my leaded race fuel, lol.
My AEM set up was acquired when only the LSU 4.2 sensors were available and I saw no reason to change.
I suspect what may have changed is on the global supply chain side.
There are a lot of different sensors now, and sources are all over the map.
Even some of the Bosch sensors are apparently made by NTK.
We'll see how this works out.... not giving up my leaded race fuel, lol.
Last edited by Mahler9th; 05-09-2018 at 07:59 PM.
05-09-2018, 05:16 PM
#4
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I believe AEM is still using 4.2 sensors in most of their setups. I know they still are on the Infinity ecu. 4.2 vs 4.9 is a difference, but not sure it matters for most.
We haven't had any problems with our Bosch 4.2 sensors, but we are on unleaded race fuel.
We haven't had any problems with our Bosch 4.2 sensors, but we are on unleaded race fuel.
05-09-2018, 08:03 PM
#5
Three Wheelin'
Thread Starter
AEM have products with Bosch LSU 4.9 sensors. They changed some products to the 5-wire 4.9's quite a long time ago.
Their AFR/UEGO controller gauges are designed to make occasional free air calibration unnecessary. Not sure that would have made a difference with the issues we have seen.
In any case, we will see how this new controller unit and NTK sensor perform in my application.
Their AFR/UEGO controller gauges are designed to make occasional free air calibration unnecessary. Not sure that would have made a difference with the issues we have seen.
In any case, we will see how this new controller unit and NTK sensor perform in my application.