stumblyjoe,

You have to INTERCEPT whatever sensor you want to tune...if you tune the smt6 with the widband on the smt6 and the narrow band going into ecm then well...your not tunning anything at all...what you haev to do is put wideband in replacment of narrowband (if you wnat you dont have to at all i think) anyway put the line out of the wideband into the smt6 and then the line out of the smt6 into the ecu so that the smt6 is between the 2 objects (o2 and ecu) this way whatever you tune will be modified by the smt6 and trick the ecu into reading differently then the o2 sensor is actually putting out!

Now that is called CLOSED LOOP TUNING...which means form idle to just before WOT is being tunned...this is a good way to do it becuase thats the way you drive in more often...you dont go into open loop on a minute bases (WOT) anyway UNLESS you got the esc1 in which case anytime your in boost above 2psi (for some reason anytime above 0psi for me) it puts it into open loop and will take readings from the maf....

Now when you intercept the MAF (levingthe o2 sensor alone) which means the line out of the maf goes into line in on smt6 and the line out on smt6 goes into the ecu. This will tune OPEN LOOP in which it will modife the MAF sensors readings it sends to the ecu....thus making sure you get that gas in thier properly!

Hope this clears things up a bit....i even impressed myself!

Now the easiest and most proven way is to tune in open loop with esc1 (thats what i am doing and am VERY happy with it)

 

OK guys, now I realize why I confused everybody. It's because I have no clue
So, my problem was that I thought you could tune closed loop for "normal" driving conditions AND tune open loop for more aggressive driving. So I guess I was completely wrong about that.
As Chris said, I guess the first issue is which tuning do I want to do. Well, I would say closed loop (because I try to be calm while driving, most of the time) except for the fact that (using the BR3) I have noticed that my truck goes into open loop A LOT. Sometimes it takes practically no engine load to put in open loop (although sometimes it stays closed under hard acceleration), and I think it is running lean when open.
With that to addition to my confusion...

 

yea mine works oddly like that as well...you have esc1?

just tune in closed loop like most of us do so we can provide the best solutions for you!

by the way what year and tranny si your truck? just so i know

 

Thanks for the help.
Right now I don't have an ESC-1, so is it REALLY weird that my truck is wanting to go into open loop a lot?
As far as my tuning questions, I am trying to progress safely. I am just worried that I am running lean when in open loop.
BTW, I have a 2002 automatic tacoma. Right now I just have the charger and SMT6, but I am planning fuel mods as we speak...

 

Ok, Weasy2k and Stumblyjoe, here's the real deal!

Nobody to my knowledge is tuning closed loop as of yet using the SMT-6. I'm the only one that has tried it, and since decided that it's not the best way to go for my application. Here's the only two scenarios for tuning our trucks:

1) Open Loop Tuning - Using this method, you have connected and altered the MAF signal

2) Closed Loop Tuning - Using this method, you have connected and altered the O2 sensor signal

Now, let's talk about Open Loop Tuning (MAF):
This is the way everyone has set theirs up to this point. When you tune the fuel analog map, all you're doing is tuning it just enough so the stock ECU can pick up the signal and maintain the 14.7:1 ratio as good as possible. Now, this is only true while in closed loop, when the ECU uses the signal from the O2 sensor to maintain the stoich mixture. Now, once you kick it into open loop, the stock ecu no longer trims or adjusts fuel. What happens is whatever the stock open loop fuel map looks like, the figures in the boxes of the analog fuel map add to it, which is how you are tuning open loop vs. closed loop.

NOTE:If you have the ESC1, you need to tune using this method! If you don't have the ESC1, you can tune using either method.

Now, let's talk about Closed Loop Tuning (O2):
This has not been successfully completed on our vehicles by anyone yet. I tried it, but due to no responses from either PP or Louie, and my recent findings, it's definitely not the way you want to tune if you are using the ESC1. Either way is possible if you don't have the ESC1. And, actually, there is no benefit to tuning O2 sensor (Lambda) when compared to MAF sensor or Open loop tuning.

Hopefully this clears up some misconceptions. I don't have time to fully explain right now, but I wanted to at least get this out to you for review, and then I'll answer any direct questions if you have them.

Chris

 

yea i understand that fully...spent the last 8 mths leanring this stuff =]....my truck is happy...runs great clean smooth...it could run better but that iwll have to wait as i slowly progress from PERFECT noboost tuning =] then ill move into making the REAL power int he boosted riegn....then timing will come last.

Davidtaco at ttora is taking his 95.5 to dyno tune it and at which point he will send me his maps as he has same setup as i do exvcept he has 330's instead of 370's but i will play with his fuel zero to get it to work with mine....im concered with non boosted portion right now as that is crucial to power in all ranges.....

anyway glad you joining the club and you will love the new power you will experience...oh after reading that you have 2002 you wouldnt be able to tune via lambda anyway because you have a different sensor i forogt what its called...not a o2 sensor i think its air fuel meter i dont knw =]...they changed it a couple years back. So to get ratio readings you need to get a standard narrow band installed into (or wideband) to see the ratios...may be a bit harder to tune without it....

i could be wrong but thats what i heard!

 

I don't doubt you understand everything, but this is what got me confused. Was this a typo? Just checking to make sure!

Chris

 

˟˟˟˟˟ yes that was oopps...god been doing to many things at once....OPEN loop damnit =]

 

OK, then clearly I didn't understand :pat:
Basically, I had it reversed. So, since I am using the MAF I am OPEN loop tuning (just have to say everything three times before it sinks into my thick skull) and it seems like the best way to do it.
Now a theoretical question, what would happen if you were using lambda tuning when it goes into open loop? Would it revert to the default open loop fuel map? or would you be "forcing" it to stay in closed loop all the time?
Sorry, if this has already been covered. This an Dr. Z's thread have so much information that I keep having to re-read EVERYTHING each time I try something, and I am a little behind the leaders. So thanks to everybody, I have learned almost too much

 

Well, not really it will only tune closed loop and when you hit into open loop the ecu stops taking information from the o2 sensor and at which point it will use its internal maps that are based off maf readings so you wont really be bale to tune this way...if you are like some people (VERY VERY rare) and never go wot that means never going to open loops that means no need ot tune up thier....but then again they wouldnt have needed fuel mods as well =]

yes maf is OPEN loop....aka you break open the closed loop cause of all the power =] thats how i made it settle in

 

As Weasy2k said, it wouldn't force it to stay in closed loop, but actually after I thought about this some more, it really doesn't matter which way you tune: either will work fine and achieve the same objective. The reason for this, after I thought abut it, is that when you go into open loop, the ECU uses it's open loop map, but in addition (in either tuning mode) will add or subtract fuel based on what cell it's in and how you have it adjusted. So, in a nutshell, there's no benefit of tuning either way.

Chris

 

the SMT5 cae in today .. so many wires ... its like a gay pride flag. ha!