It definitely is amazing progress gunzo. I know we all appreciate everyone working on the project.

People are just so excited for the product that it eats away at them and they start to focus on it way too much.

Any estimated timelines for a full launch? February maybe?

 

Just wanted to check in and see if its looking like we are all going to get an awesome Christmas present and ECU flash for the X is going to be released????

 

One can only hope...

 

Have you guys tried to eliminate the second O2 CEL? Mine is dead and hate to buy a new one.

 

Sorry .. I don't see a reason to do this for now as mine is JDM

So until someone with a USDM car start fiddling with the ROM .. its going to wait ..
.. how badly you need this done ?? does this allow running of testpipes too ??

 

I wouldn't mind eliminating that secondary o2 sensor CEL either... this will allow the running of testpipes without throwing the CEL, which would be great... to answer your question.

 

It's not a huge deal. Just saw that you were able to do this on the older EVO's so figured it would eventually be possible on the X. Considering the price and how well it works, I'm not complaining.

 

Nice write up razorlab. Thanks for the information.

 

So the high and low octane maps are for open loop. How do you change closed loop?

 

Closed loop can't be changed with a stock NB O2 sensor. NB O2 sensors can only accurately detect 14.7:1, so its impossible to use a set point different than 14.7:1.

 

So there is no map you change and just use your WB 02 to set the closed loop setting? I was reading that 15.2 is better for MPG in this thread: https://www.evolutionm.net/forums/ec...-tune-evo.html

So why try to tune to 15.2 if you can't? Am I missing something?

 

OK .. I'll work on it .. merry christmas guys ..

I'll start after new year
If I manage to solve it .. please give thanks to MJ and MrFred

 

If a simulated NB O2 sensor signal from a WB O2 measurement system is substituted for the stock NB O2 signal, then its possible to tune leaner closed loop, however the setpoint is controlled with the WB O2 sensor controller and not the ECU. Another option is to send the actual WB O2 sensor signal into the ECU, and then patch the ECU code to understand the WB O2 sensor signal. In this instance, then its possible to tune closed loop using the ECU. I'd say this latter option is a ways off for the X though. Probably at least a year away.

 

So you are saying the stock NB controls the AFR in closed loop vs the ECU in open loop? I just want to be clear then, the ECU does not control AFR in closed loop. So the NB O2 is demanding the 14.7?

I would THINK the NB is checking for 14.7 and the ECU is requesting the 14.7. But what ever. Ya I would just like to find a better way to control the cursing AFR to get better MPG.

 

The target AFR for closed loop is 14.7:1. This is built into the engine control code. The ECU uses the stock NB O2 signal to determine how close the AFR is to the target value and (the ECU) makes fuel trim adjustments (injector pulse width adjustments) to maintain 14.7:1 as air temperature, humidity, elevation, engine temperature, etc change.

So, NB O2 sensor is simply a tool used by the ECU, and its the ECU that does the controlling.

Using a simulated NB O2 signal from a WB setup to achieve leaner AFRs than 14.7:1 during closed loop is a simple and reasonably effective way to get leaner closed loop cruise.