Amazing work Mrfred. Gonna have to set this up as soon as I get my car running again (Damm Clutch!!!)

 

Now that's just cool. mrfred, you've outdone yourself this time.

I'm guessing that, at least initially, we probably won't be able to physically eliminate the front O2 sensor, for similar reasons as to why we need the rear O2 heater circuit resistor and CEL patch?

 

You can probably remove the front 02 sensor but will likely need to install a resisitor.

 

Since High temps tend to ruin WBO2 sensors, would it be fine for trims and such to put the WB02 in the rear and plug the front O2 location with a bung-plug if you were using a resistor? (good lord that sounds wrong)

 

I still have yet to see empirical data to prove this. My roommate ran his Uego sensor inches from the turbo outlet on his subaru running consistently 1650-1700F egts without any issues for 3 years. He has never replaced the sensor and it has always been very accurate. I see no reason you cannot run the sensor close to the turbo.

 

This might be true but the fact is that every wideband mfg's recommends installing the sensor quite a bit further away from the heat. Most give a specific range of temperatures that the sensor should be in. There is no reason to install a wideband 02 sensor so close to the turbo. Even if the sensor might last it places unnecessary stress on the sensor and it may fail sooner.

The sensor should be installed right around the area of the test pipe.

 

He installed it there because the Cat is in the downpipe. It was as far as he could get it from the turbo.

 

Good thing this is an Evo Forum and we don't have to worry about silly cats in DP's

 

hehe yup. Or the 4' of exhaust piping BEFORE the turbo...

 

ECU passes rear o2 test check. Pass smog while not having a rear o2 even on your car.

 

allows you to set a different closed loop AFR ---- better fuel economy.

I like it also because I can now eliminate another sensor which just means less work when I have to pull the turbo.

 

Doesn't the front o2 sensor adjust the closed loop AFR, not the rear?

 

Yes it does. The rear just does emissons. But if you are removing your front sensor, chances are you have removed your rear also.

 

Yup. I think Dudical might have confused some things.

 

Now been running closed loop cruise (v1) at 15.5:1 afr for a few days. I was anticipating idle issues, but so far, its about the same as idle at 14.7:1. What I have noticed though is that the car runs like *** when its cold. So v3 will include a min coolant temp for controlling closed loop according to the AFR map. There will be a user adjustable global closed loop afr for when the coolant temp is below the min temp. This should also help with some people's issues about their car running like poo poo when cold.

I successfully simulated v2 last night and found a few things that needed optimizing. v3 code should be complete this evening and possibly get loaded into my Evo ECU tomorrow morning for testing.