Yes, it provides open loop without a CEL.

Is there a MUT channel that provides an output of "calculated" AFR with all the corrections taken into account?

Also, does the ECU continue to use theLong and Short term fuel trims that are already in the memory or does it ignore them when you disable closed loop?

 

Yea, I might have done that. My bad

 

I will test this to narrow down an issue I am experimenting here. https://www.evolutionm.net/forums/ev...t-causing.html

I think that this can rule out that the problem I am having during cruise is related or not to Closed Loop.

Thanks mrfred!

 

I know there's a lot of other talk about open loop and solutions to running it full time, but was this particular method ever confirmed to be fully functional, without issues, and safe to use?

 

Yep, it works without issue.

 

Yes! I am using it ATM and no issues so far.

 

So as I gather it this disables the ECU from looking for activity from the primary O2 as well? I have tuned my car in open loop for a long time (as well as most of the large injector cars) and just have always done it with the load tables. Problem is even though you dont use it if the O2 dies you get the 2195 (stuck lean) code and I havent figured out how to disable that. I know that 50 isnt much for an O2 but for something I dont use it is a waste.

 

Cool.

Another question I have though. When I go to tune for the 1000cc injectors I'll be putting in, won't I still need to setup the scaling for them to work which would require referring to trims. If open loop is enabled, will it still give trims?

 

No it doesnt give trims. The process gets a little more complicated but not impossible. You need to get the car running close (it should be if its already scaled in closed loop) and make sure your WOT stuff is right first. If you start with a table that has range somewhere in the middle (lets say 10s) and then it gives you a 11.5 or whatever the idle and cruise is still just a matter of latency and sometimes fuel map.

On large injectors it makes it more drivable since its not chasing its tail in a feedback loop which seems to inevitably happen.

aaron

 

Hmm.

I may just dial it all in on closed loop first. Then once the injectors are good I'll enable full time open loop and retune the low load areas.

I should also point out that this is in a DSM, not an Evo so it complicates things a bit.

 

Its still the same. If you are using an Evo ECU you dont have to focus on trims like we have to running DSMlink or anything like that.

 

To answer my own question, yes you still will get the 2195 if the O2 is dead so this really doesnt help that situation. Tuning in open loop is still my preferred method on big injectors but it doesnt help me today

 

https://www.evolutionm.net/forums/ev...need-help.html

Do you think forcing full time open loop would fix my problem thats explained in this thread? ^^

 

My 0.02 is that it may not solve the issue completely but definately will get rid of the P0172 code.

The real benefit of running open loop is that you can see how the car fueling is performing w/o the O2 feedback and ECU Trim adjustments under idle and cruise.

 

I know nothing about tuning. Obviously, would need some1 to do it for me. Im just getting irritated with this problem. Its obviously not a mechanical problem.