WideBand o2 / Oxygen Sensor Systems from Innovate Motorsports

Why is a wideband o2 sensor better for tuning AFR than a narrowband o2 sensor? Isn’t my 1/2/3/4/5 wire stock o2 sensor good enough?

A wideband o2 sensor system will give you far greater tuning ability than a narrowband sensor.  The problem with a narrowband sensor is that it is only truly accurate at 14.7:1 AFR.  The factory will have tuned your engine to run around at 14.7:1 air/fuel ratio (AFR) at cruise and light load conditions. This is the ‘chemically correct’ or ‘stoicheometric’ (stoich for short) AFR which basically means this is the air/fuel mixture at which the most complete burn of the fuel will occur. It happens to also be the proper mixture for the catalytic converter to best do it’s job.  In other words, you car comes tuned from the factory for reduced emissions and that’s why that narrowband sensor is there.  Therefore it will be useful for tuning cruise Air/Fuel Ratio (AFR) only as long as you’re tuning for 14.7:1 air/fuel ratio.  However, under Wide Open Throttle (WOT) you’ll want to tune for somewhere between 12.6:1 and 13:1 (NA) or richer for forced induction, and the narrowband won’t tell you anything useful at that range.  Likewise at cruise you may not want to tune for 14.7:1, maybe you want better fuel economy at cruise and you want to tune to 15.5:1 or even a bit leaner possibly. Only a wideband can give you accurate feedback outside of the stoichiometric 14.7:1 reading that NB sensors are designed for, and allow you to tune for best power and best economy.

In short, a wideband oxygen sensor will give you a measurement of your Air/Fuel Ratio from about 10:1 up to about 20:1 AFR allowing you to target exactly the AFR you’re after at all times.  A narrowband can only tell you when it’s 14.7:1, and is therefore nearly useless for tuning.

Do I have the newer or older style LC-1? Should I get it replaced if it’s older?

You can skip this section if you bought your LC-1 after June of 2006.

First…  If there is a voltage differential or any other cause that would pull your 5v output to anything above 5v it could burn out the DAC on the older model LC-1.  Wired properly most people never had a problem with them but Innovate proactively made the circuit more robust, replaced faulty units and provided an updated version of the product.  Their handling of this issue was truly a class act.

The ‘older model’ LC-1’s were up until about June 2006, in white/beige box.  The new models were sold since then and Innovate updated the packaging at about the same time to a blue/black box and later still to a white/red box.  The more definitive way is to determine which model you have is to check the serial number.  The serial for the LC-1s with the analog output fix are LC11188 forward and all LC-1s that start with CLC.  Note that in  fall 2007 Innovate started using a white/red box, these are still the new LC-1’s, just using a different box design.

Bottom Line: Wiring it according to the docs is the most important thing. Not just for longevity but for accuracy as well. You don’t want a voltage differential in your readings so you definitely want to ground your LC-1 at the same point as your ECU (assuming you’re feeding the output back into the ECU) or datalogger if that’s what you’re using. Then ground the heater ground to a separate point as per the docs. This will make even the old LC-1’s last forever in our experience.

How should I wire up my Innovate LC-1 or MTX-L?

Begin by following the ‘Quick Start Guide’ that comes with the controller.  If you lost that or need a copy of it for some reason you can download it here:  LC-1 Quick Start Guide for the LC-1, LC-1/XD-1 Standalone Gauge Kit  if you have the combo kit, or MTX-L Manual for the MTX-L.

In addition, DIYAutoTune recommends:

  • Grounding the controller and the MegaSquirt together.  This is to prevent a voltage differential and will ensure accurate readings.
  • The factory EFI system’s fuel pump relay often makes a good source for 12v switched power.  This is a required source for 12v, but often a good one…
  • For the LC-1, wire the brown (analog out 2) wire to the MegaSquirt’s O2 input wire. For the MTX-L and LC-2, the default analog outputs are reversed, so you’d wire the yellow (analog out 1) wire to the MegaSquirt’s O2 input wire.

For any LC-1 purchased after June2006, that should be all you need to be concerned with when wiring it up.

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IF YOU PURCHASED YOUR LC-1 PRIOR TO JULY, 2006: Use a 470 ohm, 1/4watt resistor in between the analog output of the LC-1, and the o2 input of the MegaSquirt.  So you’ll wire the analog output from the LC-1 to one side of the resistor, and then you’ll wire the MegaSquirt 02 input to the other side of the resistor, forcing the signal to pass through it.

How should I wire up my Innovate LM-1 or LM-2?

Begin by following the ‘Quick Start Guide’ that comes with the LM-1 / LM-2.  If you lost that or need a copy of it for some reason you can download it here:  LM-1 Quick Start Guide
LM-2 Quick Start Guide

In addition, DIYAutoTune recommends:

  • If you are simply using the LCD display on the LM-1 / LM-2 to tune your car you have nothing different to do.  However, if you are routing an analog output from the LM-1 / LM-2  into the MegaSquirt you should ground the LM-1 / LM-2 and the MegaSquirt at the same point.  This is to prevent a voltage differential and will ensure accurate readings.  You might even clip the cig lighter connector wire that comes with the LM-1 / LM-2 and put quick disconnects on it, and install the same type of quick disconnect connectors on the MS Harness so I can pull power and ground from the same source it pulls from, ensuring the MegaSquirt gets an accurate sensor reading. 

Note– You do not ever need the 470 ohm resistor with the LM-1 or LM-2.

How do I configure TunerStudio for the Innovate LC series, MTX-L, or LM-1 / LM-2?

For a long time we guided customers on how to re-program their LC-1 / LM-1 / LM-2 to output a slightly different signal from default.  The goal of this was to increase the resolution of the signal in the range of AFR most users will spend their time in.  We used to recommend programming the output you were using to send a signal that represented a 10-20:1 AFR from 0-5v.  While in theory this is great and does increase resolution a bit, in practice it’s not really needed and is probably more trouble than it’s worth for most users.  We now recommend leaving the analog outputs on your LC-1 / LM-1 / LM-2 at their default settings (which is 0v = 7.35:1 AFR, and 5v=22.39 AFR).  Proceed to configure the TunerStudio tuning software to allow your MegaSquirt EMS to properly talk to your LC-1 / LM-1 / LM-2 do the following:

MS1/Extra:

With your TunerStudio project open, go to:
File > Project > Project Properties and click on the Settings tab
Under EGO O2 sensor, chose the right option (Innovate LC-1 Default) for your wideband in the drop down menu and click Ok.  TunerStudio will quickly restart and take you back to the main dashboard.

Next, click on the Basic Settings tab and chose Exhaust Gas Settings.  You will need to change your EGO Sensor Type to wideband.  Burn the change to your MegaSquirt.

Your AFR Targets Table will open underneath the More Settings tab.

MS2/Extra:

With your TunerStudio project open, go to:
File > Project > Project Properties and click on the Settings tab
Under EGO O2 Sensor, chose the right option (Innovate LC-1 Default) for your wideband in the drop down menu and click Ok.  TunerStudio will quickly restart and take you back to the main dashboard.

Next, click on the Basic Settings tab and chose EGO Controls.  You will need to change your EGO Sensor Type to wideband or dual wideband as appropriate for your setup.  Don’t forget to burn the change to your MegaSquirt. Lastly you will need to go to the Tools menu up top and click on Calibrate AFR Table.  Chose your sensor type (Innovate LC-1 Default) in the drop down menu, and click on Write to Controller.  This is a one way flash, so don’t be alarmed if your settings don’t ‘stick’ in this menu after you’ve sent them to the controller.  After the write is complete, click Close.

Your AFR Targets Table will be under Basic setup > AFR Table 1

MS3:

With your TunerStudio project open, go to:
File > Project > Project Properties and click on the Settings tab
Under EGO O2 Sensor, chose the right option (Innovate LC-1 Default) for your wideband in the drop down menu and click Ok.  TunerStudio will quickly restart and take you back to the main dashboard.

Next, click on the Fuel settings tab and chose AFR/EGO Controls.  You will need to change your EGO Sensor Type to wideband.  Most setups will use a single sensor with the input received on DB37 Pin 23.  If this is the case for your application, enter 1 for Number of sensors and set your EGO Channel to Normal EGO.  This is a pink wire labeled “O2” on our harness.  If you are running multiple widebands, you will be able to set that up in this menu as well.  Don’t forget to burn the change to your MegaSquirt when finished.

Lastly you will need to go to the Tools menu up top and click on Calibrate AFR Table.  If  the option for Calibrate AFR Table is grayed out, you will fist need to go to Tools > Un/Lock Sensor Calibrations, choose Unlocked, and Burn and Close.  Then you will be able to access the Calibrate AFR Table menu under Tools.  Choose your sensor type in the drop down menu (Innovate LC-1 Default), and click on Write to Controller.  This is a one way flash, so don’t be alarmed if your settings don’t ‘stick’ in this menu to be later viewed again after you’ve sent them to the controller.  After the write is complete, click Close.  If you desire, you can lock your sensor calibrations again by visiting the Tools > Un/Lock Sensor Calibrations menu again.

Your AFR Targets Table will be under Fuel settings > AFR Table 1