Someone mentioned that ECUs in the Z are self-learning, and that even with piggy-bank ECUs and the like, the OEM ECU will still correct all of the A/F settings and revert it all back to its original state. This person is someone who is extremely familiar with Nissan vehicles, so I didn't argue with him.

Another person said:

So would that make things like a reflash and a piggy back tune useless? Or are they completely wrong? Again, both are really well respected guys on another Nissan forum, so I figured I'd try to find some more info about this.

Has anyone ever done a tune and dyno, and gone back to re-dyno their car weeks later just to see if those numbers stuck?

 

When SGP tuned my UTEC, Mark inhibited the self learning stuff with the Cipher software.

So yes, I think the ECU will learn around the piggy back. I noticed that my car ran better the first time I turned the key than it did every day there after(before my tune).

 

I don't think you can disable any "learning stuff" with Cipher.

You can flash new targets with Osiris, though. That way the ECU learns towards your desired settings... or install a stand alone system that the ECU can not change.

 

My UTEC tune has stayed fairly consistant after 6 months. It varies a bit based on weather but is always right around were I left it.

 

So can the ECU override the UTEC?? My TS flash has stayed consistent as well. But sometimes it varies based on weather.

 

Are you FI? FI uses MAP and it has its own table for Fuel and Timing, how can the ECU interrupt when Utec is taking full control of your Fuel and Timing on load?

 

Me? I'm not FI. But I didn't know if the ECU had some way of going around the UTEC or not.

 

If you put the UTEC in open loop fueling it uses it's own base tables so there isn't a way for the ECU to override it.

 

+1

 

So even if you're not FI you can still use open loop??

 

Yes, only the MAP is recommended for FI only and I am even going to try that N/A. You also have to be in open loop to extend the rev limiter.

 

What about the timing?? I know most run 17 BTDC. Is that is that through the entire rpm range or does it vary by car?? I almost think I know the answer to this question.

 

The UTEC is not a pigggyback ECU. It is a parallel ECU.

JET

 

I'm inclined to believe that the ECU adjusts eventually to a mod. After I had the 5/16 installed, I felt a bit of a gain. But days later after about 100 miles of highway driving and some WOT, I noticed a much more notable gain - almost as if the spacer had been broken in. Traction became much looser in 1st and 2nd, where as before I had no such problems.

I had numerous people suggest to me that the Z's ECU simply learns to adjust to settings after some driving. I doubt it replaces a proper tune, but it's still nice to know that, allegedly, our ECU is always actively monitoring and adjusting.