MTX-L Wideband Question

[turbobird14]

Hey guys i have a few questions reguarding the install of this kit.

1991 Eclipse GS-T FWD

First the wiring: 5 Wires -
Red - 12V Switched Power
Black - Ground
Yellow and Brown - Analog 1 and 2
White - Connect to a Headlight Power Wire (a wire that supplies power to the headlights) - Dims the Gauge at night
^ This is where i have a question... Would i be able to hook this up here and have it work the same way as described in the write-up? Randy Nuckels - aftermarket gauge lights to factory dimmer switch. If not what wire should i tap into?

The other question i have is, will this directly replace the o2 Sensor or do i need to drill and weld in a bung for this? I have read on a few that people have taken out the front o2 on the housing and just installed it in place of that. If thats the case will it be a direct connection to the existing o2 connector? Thanks for all the help!

 

[lil corb]

If you have link or any other program that let's you use the wideband as a narrowband simulation then I would put it the front o2 location. If not somewhere close to the beginning of the downpipe would work 2nd best in terms of accurate reading. Just make sure you have no exhaust leaks.
Mine is in the front location using nbs with link.

As for the white wire, I had to use it as another ground. When I had mine spliced to headlight dimmer I kept getting a e9 (low voltage) code so mine doesn't dim. But its not my DD so I'm ok with that.

 

[turbobird14]

Well i just ordered a new downpipe with a wideband bung already welded in so that will work!!! As far as the white wire, what could i possibly tap into and where would it be the best? It says NOT to tap the headlight dimmer wire because it will throw that code, so thats probably why you were getting the low voltage code!

 

[Dsmkauai]

Mtx-l has narrow band sim built in bro. So you can run it in the front o2 location. And it's not plug and play with the stock harness. You will need to hard wire in power and ground and tap into pin 76 on ecu to use narrow band sim or if you have tuning software to log the wideband. I never hooked up the white wire on mine to dim gauge and it didnt bother me one bit meaning it wasn't unbearably bright.

 

[c2ypt1c]

Would i be able to hook this up here and have it work the same way as described in the write-up?

The manual explicitly states not to connect it to a dimming switch. Wire it to headlight power. The cig lighter has a light that illuminates when the headlights are on, you may be able to use that.

The other question i have is, will this directly replace the o2 Sensor or do i need to drill and weld in a bung for this? I have read on a few that people have taken out the front o2 on the housing and just installed it in place of that. If thats the case will it be a direct connection to the existing o2 connector? Thanks for all the help!

It is not a direct connection to the existing o2 connector. If you replace your front o2 (narrowband) with the mtx-l (wideband), you will need to wire it up for "narrowband simulation." The brown mtx-l wire supplies a narrowband signal (0-1v) and you will have to wire this to pin 4 (o2 on a 1g, I believe) on the ECU harness.

IMO, I think it would be best for you to keep your factory o2 in place and run the mtx-l further down in a new bung (before the flex section). It should only cost around $30 at a muffler shop for the welding.

 

[ed1380]

I'm running my mtx-l in the stock o2 housing. Its the same o2 sensor used by 02-05 Jetta 1.8t's and they don't have a problem with then going out. And if it ever does, just get one from eBay or a junkyard

 

[Dsmkauai]

Op do you have a 95 or a 91 gst? Because your profile says 95 and your asking about a 91. Just want to clear this up so you get the proper info on what pin to tap into.

 

[turbobird14]

Thanks for all the help guys!

Op do you have a 95 or a 91 gst? Because your profile says 95 and your asking about a 91. Just want to clear this up so you get the proper info on what pin to tap into.

Its for a 91 GST - I had a 2g a while ago when i was on here and just noticed that!

The manual explicitly states not to connect it to a dimming switch. Wire it to headlight power. The cig lighter has a light that illuminates when the headlights are on, you may be able to use that.

Ya im an idiot, because i just told the first responder why his wouldnt work...

 

[LiquidX]

My personal experience, while the NBS is a great feature, I still recommend using a stock narrow band sensor as well.

You have to beer 100% sure you don't have any exhaust leaks jacking up the signal. Also the narrow band sensor accurately tells the switch points showing the stoich voltage which is something Tom and Dave from ECMLink really like to see.

 

[c2ypt1c]

My personal experience, while the NBS is a great feature, I still recommend using a stock narrow band sensor as well.

You have to beer 100% sure you don't have any exhaust leaks jacking up the signal.

Not to mention, if the sensor goes out of whack and needs calibration, without link, there is no way to lock the ecu in open loop until the sensor is recalibrated, which will make the car run like crap during closed loop operation...

 

[red_devil]

Not to mention, if the sensor goes out of whack and needs calibration, without link, there is no way to lock the ecu in open loop until the sensor is recalibrated, which will make the car run like crap during closed loop operation...

Well saying that my MTX-L decided to loose calibration during a 8 hr drive, it would cycle from 9.0 to 20.0 but the car still ran fine and got the same gas mileage as before. I do recommend that if you have the sensor mounted in the front o2 sensor then make the main harness connector in a easy to reach spot so you can re calibrate it quickly.

 

[ed1380]

My personal experience, while the NBS is a great feature, I still recommend using a stock narrow band sensor as well.

You have to beer 100% sure you don't have any exhaust leaks jacking up the signal. Also the narrow band sensor accurately tells the switch points showing the stoich voltage which is something Tom and Dave from ECMLink really like to see.

If there is a pre-o2 leak it will affect a narrowband and wideband sensor.

Also the narrowband signal(voltage) from the mtx-l is the same exact signal(voltage) that the stock o2 would provide the ecu, so when tuning you cant tell the difference between stock o2 or a simulated signal from a wideband

 

[iBoostDSM]

I'm bringing this back from the dead. On my 1g I have my mtx wideband mounted on a bung on the downpipe NOT it the front o2 sensor location. To log it on dsmlink v3 would have have to tap into pin 4 wire? Like the link below?

How To: Properly Tap Into Wires - Club3G Forum : Mitsubishi Eclipse 3G Forums

 

[snowborder714]

Instead of using that method, just cut the wire as far away from the ECU plug as possible and wire the new one straight in. Then tape/heat shrink the end that disappears into the harness.

The yellow wire is the one you want to tap into pin 4. This will render your front o2 sensor useless though and you will have to enable narrowband simulation via ECMlink.

 

[c2ypt1c]

On my 1g I have my mtx wideband mounted on a bung on the downpipe NOT it the front o2 sensor location. To log it on dsmlink v3 would have have to tap into pin 4 wire?

If you plan to keep the factory o2 in place and wish to log the mtx-l as an additional input (without narrowband sim), then you don't want to wire it to pin 4.

Here are your options:

1G ECU
- EGR Temp Input (ECU Pin 15) - Not 100% compatible with some sensors, such as the AEM WB

- IAT Input (ECU Pin 8) - see IAT/Baro Notes below

- Baro Input (ECU Pin 16) - see IAT/Baro Notes below

- Front O2 (ECU Pin 4) - Only usable when "Open Loop" option is selected (V2 or V3), or narrowband O2 simulation is enabled (V3 only).

- Coolant Temp Input (ECU Pin 20) - (V3 only) - This will leave the car in "Open Loop". "Lock Coolant Temp" must be selected, to work properly. Use only as a last resort and only temporarily unless you fully understand the issues.

In this case, I would go with the EGR (pin 15), and you don't need to splice into it. Just cut that sucker off and wire it in. However, the EGR input might require a buffer circuit on it so, if you do decide to go this route, you might want to look into that...

 

[iBoostDSM]

Instead of using that method, just cut the wire as far away from the ECU plug as possible and wire the new one straight in. Then tape/heat shrink the end that disappears into the harness.

The yellow wire is the one you want to tap into pin 4. This will render your front o2 sensor useless though and you will have to enable narrowband simulation via ECMlink.

So if I was looking to log the wideband and simulate narrowband, which I am, I would cut the pin 4 wire and then connect the yellow wire from the wideband to the pin 4 wire on the side with the plug that goes into the ECU? Then tape up the brown wire, or do I need to use that too, and the other side of the pin 4 wire? Just trying to make it as clear as possible for myself so I don't mess something up.

 

[snowborder714]

You've got it.

 

[iBoostDSM]

You've got it.

Thank you so much!

 

[zack13277]

So I'm using the Front o2 bung to put my MTX Wideband into, I just splice the yellow wire to pin 4 on the ECU and could I still use the brown wire for any thing or not?

 

[snowborder714]

What would you need the brown wire for?

 

[Jesse2012]

Instead of using that method, just cut the wire as far away from the ECU plug as possible and wire the new one straight in. Then tape/heat shrink the end that disappears into the harness.

You mean making it so the wire from the wideband harness runs directly into the ecu, and the original wire on the factory harness is disconnected right? I've always been confused about this

 

[zack13277]

I just figured they put a brown wire on the wideband, so could it be used for something? Or is it just the same signal as the yellow wire and the brown is used for other vehicles?

 

[snowborder714]

You mean making it so the wire from the wideband harness runs directly into the ecu, and the original wire on the factory harness is disconnected right? I've always been confused about this

Correct. The part of the wire that disappears into the harness won't be used anymore and the wideband will be connected directly to a portion of the wire that comes out of the plug that goes into the ECU.

I just figured they put a brown wire on the wideband, so could it be used for something? Or is it just the same signal as the yellow wire and the brown is used for other vehicles?

The brown wire on the MTX-L is for narrowband sim if you need it. Or it can be reprogrammed to output a wideband signal and used to feed the signal into a gauge.

 

[zack13277]

Alright, so to keep it simple just use the yellow wire and call it a day. Thanks a lot.