MTX-L Wideband behaving odd

Search is your friend they say. And I found some threads touching this issue but nothing that completly solves my problems. With that said "I'm sorry for MAYBE doing a double post"

Now to my Issues.
I installed a Innovate MTX-L Wideband last year at this time. Took out the old OEM Lambda and just popped this new Bosch into the existing bung in the downpipe. MTX-L Narrowband output goes to blue? wire on OEM lambda loom and Wideband 0-5V loggingwire goes to ECU.
All was fine, MTX-L performing good numbers 14,7 @ Idle and 10.3 (about) AFR @ WOT. In December last year I noticed that once in a while @ startup with warm engine Idle AFR wasn't 14,7 anymore rather 15,8 AFR. But a quick dip on the throttle brought it back to 14,7 AFR again.

Now when I doing a Cold start in the morning when the car's been standing overnight AFR rises from around 11 AFR to 14,7 and stays there (Open Loop, right?) BUT every time I do a Warm Start (between 10min to 4h after last use) I get a AFR reading of 17 and it stays there... ALWAYS... If I don't touch the throttle AFR stays @ about same reading. Fluctuating between 16,6 - 17 AFR. If I dip the throttle and keep revs above 3500rpm for just a second AFR reading comes down back to normal 14.7 but jumps around between 14,1 - 15 AFR.

When I driving my car normally (cruise) AFR reading fluctuates between 13,2 - 17,5. @ WOT I get a AFR reading of 11.2 (about)

Have checked for air leaks, found nothing. Did a Exhaust test earlier this week. Lambda was spot on 1.005 CO = 0.18% O2 = 0.4 HC=128

What could be causing this rather odd behaviour? Faulty Lambda sensor? It have been calibrated regularly 4 months apart and 3 times this week.
I have Evoscan but I'm rather noob to that Software. Did a small log when the car was in my garage the other day.

How old is the sensor? My old sensor was playing tricks when it was dead - although it had different symptoms to yours (it was reading above free air).

It could also be that the engine is just putting in enough fuel for what it needs, but it's just leaner than what you expect. I'll see what mine does after a warm start - from memory though it sits around 15ish AFR idle.

My car exhibits the exact same behaviour, temporarily idling lean on a hot engine when started. I also have a MTX-L.

That said, I dont believe it to be the MTX-Ls fault. My car would do this before I fitted the wideband kit, its only after fitting the gauge do you become aware of whats happening. I believe it to be an ECU issue, there are various enrichment tables to control such behaviour based on coolant temperature. I'll take a look at the tables when I'm next on my PC.

I'm guessing the behaviour is also linked to the cat converter warmup table as well?

The Sensor is just under a year old. I e-mailed a Innovate retailer and they wanted to change the whole thing, Sensor and Gauge just to be sure. They said they have had some issues with failing sensors on the MTX-L.
Yeah! Cat converter warmup table is erased from my ECU setup. So no CAT warmup anymore... Did it in the autumn last year.

Somebody said It could just be a grounding fault but I have moved the grounding wire around and nothing exceptional happens.
I have grounded MTX-L @ OEM Lambda signal Ground ( White wire ) and I'm taking +12V Power from OEM Lambda Heater (Black wire).

I have attached my latest EvoScan Log if someone who's not so noob as I wanted to take a look... As I see it Oxygen Feedback does not wake up immediately, It takes about 2 - 3 min for it to start correcting the readings. If I've seen right, it corrects a lean mixture with a LEANER mixture... huh? but... Yeah IDK.
Somebody educate me.

Remember that the sensor needs to warm up. I would take the offer up on replacing the entire thing if it's under warranty.

Also try resetting it completely - the narrowband emulation table may be screwed up.

Quote:

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Originally Posted by SpoonCivic

The Sensor is just under a year old. I e-mailed a Innovate retailer and they wanted to change the whole thing, Sensor and Gauge just to be sure. They said they have had some issues with failing sensors on the MTX-L.
Yeah! Cat converter warmup table is erased from my ECU setup. So no CAT warmup anymore... Did it in the autumn last year.

Somebody said It could just be a grounding fault but I have moved the grounding wire around and nothing exceptional happens.
I have grounded MTX-L @ OEM Lambda signal Ground ( White wire ) and I'm taking +12V Power from OEM Lambda Heater (Black wire).

I have attached my latest EvoScan Log if someone who's not so noob as I wanted to take a look... As I see it Oxygen Feedback does not wake up immediately, It takes about 2 - 3 min for it to start correcting the readings. If I've seen right, it corrects a lean mixture with a LEANER mixture... huh? but... Yeah IDK.
Somebody educate me.

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I am not sure the original O2 sensor wiring is a good place to GND the mtx-l as the O2 sensor will be connected to the ecu. So the mtx- l will be getting it GND path through a massive loop of wire and the ecu then through the ecu loom as well. Just connevted to the nearest chassis screw.
For a test.

They actually say in the manual for the Innovate LC-1 (and probably the MTX-L as well) that you MUST ground the heater and unit ground at the same location - otherwise you end up with sensor accuracy issues.

Quote:

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Originally Posted by wintertidenz

Remember that the sensor needs to warm up. I would take the offer up on replacing the entire thing if it's under warranty.

Also try resetting it completely - the narrowband emulation table may be screwed up.

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Yeah, Resetted the whole ECU (took negative of the battery for two hours) havn't tested yet if it worked.
But how to do a complete reset? Is that the same as Re-Calibrate? or what?

Quote:

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Originally Posted by wintertidenz

They actually say in the manual for the Innovate LC-1 (and probably the MTX-L as well) that you MUST ground the heater and unit ground at the same location - otherwise you end up with sensor accuracy issues.

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I have noticed that if MTX-L is grounded @ OEM sensor ground (white) the reading jumps around less. Is that what you meant?

Quote:

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Originally Posted by wintertidenz

They actually say in the manual for the Innovate LC-1 (and probably the MTX-L as well) that you MUST ground the heater and unit ground at the same location - otherwise you end up with sensor accuracy issues.

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i have just fitted my MTX-L and all you connect is power (perminent 12V from stereo, switched 12V ignition , GND direct to chassis), Narrowband output (to original Blue sensor wire) that is all you need.
the manual says 12V battery 12 ignition , gnd to chassis, narrowband to original narrowband sensor position.

there is a wideband output and a headlight dimmer signal, but these are not required to make things work.

everything seems to be working fine.

Carl - you will need to run the LM Programmer and completely reset the calibration and narrowband emulation.

You need to at least ground the MTX-L to the same location as the ECU. Any slight variation between grounds will cause it to read wrong.

Okay... Will try that out.
Hmmm... Just to be sure. Where is the ECU grounded? Could it be Left side of center console, on the bracket holding the ECU? In my case I see a thick wire (looks like a coax cable) equipped with a brass-looking ringconnector. Or is this the ground for the Radio Antenna? Cable seems to go away from the ECU and under and up to the "cooling unit".

BTW. Thanks for all the help... I appreciate it.

I would ground to the bracket on the ECU if it's a metal case ECU, or where the nut goes to secure the ECU in place.

I've done mine through the O2 sensor cabling itself, but the next best place would have been a lug under the nut just mentioned.

Also - if in doubt, clip the ground wires back slightly and resolder to a lug. You may have a bad joint that's only showing now.

I have a Plastic case as my Leggie is a late ´01 MT Type S.
But Yeah, I'll reroute my groundwire to the ECU grounding lug just too be on the safe side
Many Thanks! :2thumbsup

hi i have the MTX-L PLus with AFR gauge and bit unsure as to wiring it reading this post @Davezj have you wired the red wire to your constant 12v supply and to the ACC 12v on ignition at the stereo and the yellow wire to the blue wire on the ecu for narrowband? and for anyone else with this is it ok just to replace it with the factory one as i dont have access to a welder to add bung included


cheers any help much appreciated

hi can someone who has this wideband please clarify if this setup works or the setup you have that works with this brand i have the MTX-L PLus with AFR gauge and bit unsure as to wiring it reading this post @Davezj have you wired the red wire to your constant 12v supply and to the ACC 12v on ignition at the stereo and the yellow wire to the blue wire on the ecu for narrowband? and for anyone else with this is it ok just to replace it with the factory one as i dont have access to a welder to add bung included


cheers any help much appreciated

The discussion here related to the MTX-L (not the PLUS version) however the wiring appears to be the same.

Do you have the manual? https://www.innovatemotorsports.com/...X-L%20PLUS.pdf
Check the wiring instructions on pages 3 and 4.

Red - switched 12v supply
Black - ground
White - to a switched light source (to dim the gauge when lights are on (optional))
Yellow - narrowband output to blue wire on O2 sensor plug (ECU side)

:happy:

thanks is it better to have the oem o2 is well or can i just use the wideband and put it in the factory spot?

it depends. The standard O2 sensor is a very reliable source of info for the ECU and never needs to be recalibrated. The MTX-L sensor can do a good job emulating the standard O2 sensor but if the wideband goes out of calibration it will affect the narrowband output.

Some people remove the standard O2 sensor and some add an extra bung and run both sensors.

Remember that a wideband sensor is an aid for tuning, not a performace enhancing modification.
:happy:

ok cool il run both sensors thanks for the help :)