Kicking this around. I have some reversion with v&h bss pipes on my softail at certain loads and rpms. This of course screws with afrs from the O2 inputs. Would it not make sense to run a map, write the fuel offsets at 3-4 times over a month, and then just run it in open loop from there? While auto tune on the most part does a good job of establishing a good map after offset writing, further closed loop operation while minor changes are made may not be worth unstable afrs in reversion and the possiblity of an O2 sensor crapping out on a long trip. Opinions are welcome.
Ron

 

Theoretically it should work. It would be YOUR custom map.

 

I was told by T-max, that box is always checking and changing "if necessary" so maybe it thought it was necessary.

 

Yes it is,but in some conditions it may not be adjusting for what's best like when exhaust reversion tells the O2 sensors to adjust, but the it will be wrong. While auto tune does work, there are conditions where it can work against correct afrs. Things like exhaust leaks will may that cylinder richer than it should be. Delutes the oil with fuel and washes lube off cylinders. This should not happen with open loop. It will continue on with the exhaust leak, but the set map afr won't change. I'm just trying to get a handle on the best of both worlds, with both function and reliability. I don't care about slight afr adjustments that auto tune does during temp and humidity changes, and once the map has been dialed in, those changes will be small indeed. What started all this is over the year of using it, I've noticed that first run of my map the bike runs the best. Then autotune works it's magic and decel pop starts at low rpms. That I can manually edit out but the coasting in third gear in town with reasonable rpm and light load the exhaust starts cracking and popping. This is where the reversion must be happening and the O2s have altered the afrs enough at that point to cause this. No way to stop this with autotune in play unless I change exhausts from what I can see. Again, open loop may eliminate this. Don't know for sure?
Ron

 

Sounds like they need a feature where you can tell the TMax not to autotune in a range you specify. I think the DTT system can do that. Maybe suggest it to Zipper's and see what they say. Won't help you for now of course.

You should be able to play with the AFR settings to get it to dial in where it corrects properly for the reversion. It would take lots of monitoring to figure out what's going on. Not very easy to do with the TMax.

 

Planning on a 113 Headquarters build next year. More cubes, different cam and new map. I think I'll wait until then. Don't want to strap on the laptop on this stock build as it will likey suffer a head crash from this slipped crank vibrating pos. Zippers did recommend a map for the 110ci for use on the 113ci Sounds like a whole new ball game then.
Ron

 

I like the DTT system. I like how it uses the MAP sensor for timing advance, but even better, last I knew, the current model can keep a running log of, like the last half hour or so, and can be configured to quit logging so much time after an error code is thrown. Neat stuff, for sure, but I can't see me needing more than the stock Delphi tweaked by the TTS.

To the original post, I'd say that if the TMAX won't let you go sans auto-tune at some few specific places, it sure wouldn't hurt to just disable the auto-tuning altogether once some fine-adjustments are made to a base map if that's what you have to do.

 

What I typically do is once we get the tune finalized, I go into the closed loop settings and change the session and max values to 5%.

 

That reminds me. I need to back off the session learn, as I had raised it to learn quicker at one time. Anyway, according to zippers, a failure of one of the O2 sensors would not be that dramatic. It would run on the last known afr. Since nowhere in my map afrs is a condition that is too rich, or too lean that I couldn't continue on my ride under normal loads and rpms if that's the case. Anybody had one fail to support this claim?
Ron