Blayton

So I just installed an Innovate Wideband in my car because I'm about to switch over to megasquirt. Currently the stock ecu is still in the car, so I wired the brown narrowband signal to the factory plug. The car is an 05 1.8 so the o2 sensor has 4 wires. I spliced the brown narrowband to the blue wire on the plug and plugged it back in the car. The wideband works perfectly and displays the afr, but I get a check engine light P2507 (ECM/PCM Power input low. If anyone knows what I can do to get rid of the code I would greatly appreciate it.

Blayton

Ok, well apparently the "room" fuse was busted, which gave me that CEL. But now, I am getting P0031, which is telling me that the Heater for the O2 sensor is faulty. As you guys know, the Innovate has it's own heater circuit. So the factory O2 Sensor heater wires are taped up currently not being used. Have any of you guys experienced this? Or know a way to fix it?

DNMakinson

iTrader: (3)

My approach was to pay $20 to local muffler shop to add a bung for the Innovate. Continued running the full stock system, but had the wideband and gauge to learn what the stock system did.

Success, but no info on heater wires

So, calling @shuiend to discuss what he did to prevent the heater issue.

EDIT: This is the search entry I used to find info on your subject, better than searching directly in the forum: Google in this format, "site:miataturbo.net innovate narrow band"

Blayton

I did find this on Miata.net but I'm still confused about what is said to be done.

eddyc49

The ECU needs to think the heater in the o2 sensor in working. Joe Perez posted an image previously from the FSM that showed the front o2 heater resistance is 5.6 ohms.
Wiring a 6 ohm resistor across the clipped heater wires should satisfy the ECU. Keep in mind that will draw about 2 amps so the resistor will need to dissipate at least 24 watts.

Edit: the 5.6 ohms was for nb2, don't know if others the same.

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Blayton

So this should work? And from what I have researched, the heater circuit is the two black wires, correct?

Blayton

For anyone reading this thread with the same problem I had, the 6 ohm 25W resistor did not solve the problem. I just dealt with it until my Megasquirt came in.

eddyc49

That's really disappointing. I was going to try that once my motor is back in (for science). I still might to see if there isn't some difference in result.

Michael Chandler

I believe that both black wires are grounds. So I think the resistor should be between the white and black wires. I'll try it for science. And to get this CEL to turn off.