Every ~5k km's my wideband o2 sensor starts dying and I have to replace it. It starts intermittently freezing at random values for some seconds before recovering again. Then slowly over time it starts freezing more often and for longer periods, until it just stays at the same value almost all the time. I replace the sensor and everything is fine again, for a time...

Setup:
Innovate Motorsports MTX-L Plus
Always replaced the o2 sensors with genuine Bosch LSU 4.9 sensors
Using the stock primary o2 sensor location (had stock header before, now a heat wrapped TODA rep, happens with both)
Stock o2 sensor is removed, using the MTX-L Plus narrowband simulation instead
Power and ground for the MTX-L Plus wired directly from ECU power and ground
Stock ECU, ~14.9 AFR cruise, ~12.0-13.5 AFR WOT
Car is N/A

Any ideas on what I can do to solve this? Anything I should change?

I am thinking the sensors might keep dying because of temperature shock from heating the sensor with moisture on it.
Does the MTX-L Plus just have a shit o2 sensor heating strategy?
I try to always immediately start the engine as soon as the ignition is on position III, so the sensor never gets pre-heated without exhaust flow, but that doesn't seem to help.

 

This is what I suspect, at least it seems to be the most logical next step to change.

 

100% opinion however, If you pay attention to how much more reliable OEM O2 sensors are vs aftermarket, I more and more believe it has to do with the O2 sensor controller and the algorithm behind sensor’s operation and heating as you had mentioned. Not the sensor itself, whether it’s LSU4.2 or 4.9.

All aftermarket Widebands have controllers, such as AEM (controller built into the gauge) or their in-line O2 meant to feed directly into a ECU, or ProSport’s Wideband with external controller box, or AEM Infinity’s LSU4.2 onboard controller or innovates (whatever they use) just doesn’t have the same self-preserving algorithm that the OEM ECU O2 controller has.

It’s most most likely not the sensors but the O2 controller responsible for the pre-heating and the rate it pre-heats the sensor at, that’s responsible for the failures. Sounds like a bad O2 controller to me, as long as your wiring is good.

P.S. also, FYI, all you’ll get with 4.9 is just a more reliable reading over a longer period of time but 4.2 and 4.9 are both great.

I had beat the living crap out of my sensors with cold start tuning (I have LSU 4.9 with AEM x-gauge and AEM Infinity LSU 4.2) and they survived for years before they had to be replaced. My previous wideband was a ProSport with questionable controller box, yet with a stand-up LSU 4.9 sensor it lasted me for 7+ years.

I had a brand new x-gauge AEM fail on me, AEM admitted to it, and sent me a new gauge ASAP. Great service but once again, it’s not the sensor that failed, it was a controller chip soldered onto the gauge board. Who knows what damage or by how much it has shortened my LSU 4.9 O2’s life by.

That’s why I run 2 different sensor models with two different controllers and feed them both to the ECU then watch the delta between the two.

 

I agree with @EOE . The Innovative widebands have been nothing but trouble for me. I went through 3 different O2 sensors before I replaced the box, and then bought another one for a different car, and went through 2 O2 sensors on that before I gave up and bought an AEM and haven't had an issue since. My original wideband that I bought for my S2000 when I went turbo in 2006 ran well for 5-6 years for each O2 sensor, and then these newer ones have been a lot less reliable.

 

Thanks for the replies all, looks like the best thing to try will be changing the controller/gauge then.
Will probably get an AEM UEGO. Not the X-series but the classic one (30-4110). The X-series doesn't support narrowband simulation for some reason.

Also, one interesting thing I read in the AEM UEGO instructions while doing some research was this
Maybe the stock primary o2 location isn't the best spot?

 

I've been using a PLX wideband for many years now and it's been working perfectly so far.
Got it installed in "stock" orientation on my Toda header.
I think it's got a narrowband output as well but I never used that.

 

Get a better WBO2. These can also use NTK sensors which are quite a bit more reliable.

https://www.bmotorsports.com/shop/in.../cPath/103_646

 

Yeah gonna get rid of the Innovate and get something people have actual good experiences with

 

Don't go AEM if you're looking for reliability. I love my AEM and have a few, but people have massive problems with them killing sensors. Some within minutes of operation. This may be due to faulty sensors, but it could also be due to the design of the meter. I've run an older NTK AFM (these are made by ECM - Home) in my 9-7X. It's been perfect even after years of abuse. This exact model is no longer made, but Ballenger has taken that design, updated it, and now sells it under their own name. ECM makes some of the best, calibration grade WBO2s. The only other WBO2 I would consider would be one from the manufacturer of a standalone EMS (Emtron, Link, Maxxecu, etc.). The WBO2 controls integrated into the AEM Infinity are also good.

Tim

 

Already bought the AEM. What convinced me to do that was the pretty large amount of posts I found on other forums of people specifically having problems with a MTX-L, then switching to an AEM and all of their problems going away. I agree that high-end (OEM like) controllers or controllers with standalone ECU integration will be better, but for the price of just 2 replacement sensors (of which you get one with the controller, so actually it's just the price of a single sensor) I am willing to give the AEM a shot first.

The stuff on Ballenger's website does look really nice though. Although I dislike that they are not being supplied with a regular 52mm gauge. At least from the entry-level wideband controllers, Ballenger only sells the AEM, that might mean something good haha.

If the AEM turns out to to be unreliable, I might actually finally fork up the cash for a Haltech standalone. Been wanting to do that for a long time, but the high price just keeps stopping me from following through with it.