Power Vision Information Thread
Cruiser
Joined: Jan 2011
Posts: 125
Likes: 0
From: Rowlett, TX
Can someone explain what the fuel and idle trims are, and when they need to be reset (and when they don't)? I thought I understood this, now I'm not sure!
One post, way back, suggested they needed to be reset before logging. I mentioned it in a later post, and a subsequent reply said that wasn't necessary! Now, with the latest firmware, every time we flash a tune, the PV asks if we want to reset the fuel trim. But then it says its only necessary if we change anything to do with the air/fuel mixture (or maybe it says VE tables...I can't remember exactly).... Well, isn't that almost every time we flash a tune? What is actually happening when we reset these trims?
One post, way back, suggested they needed to be reset before logging. I mentioned it in a later post, and a subsequent reply said that wasn't necessary! Now, with the latest firmware, every time we flash a tune, the PV asks if we want to reset the fuel trim. But then it says its only necessary if we change anything to do with the air/fuel mixture (or maybe it says VE tables...I can't remember exactly).... Well, isn't that almost every time we flash a tune? What is actually happening when we reset these trims?
Advanced
Joined: May 2011
Posts: 66
Likes: 0
Can someone explain what the fuel and idle trims are, and when they need to be reset (and when they don't)? I thought I understood this, now I'm not sure!
One post, way back, suggested they needed to be reset before logging. I mentioned it in a later post, and a subsequent reply said that wasn't necessary! Now, with the latest firmware, every time we flash a tune, the PV asks if we want to reset the fuel trim. But then it says its only necessary if we change anything to do with the air/fuel mixture (or maybe it says VE tables...I can't remember exactly).... Well, isn't that almost every time we flash a tune? What is actually happening when we reset these trims?
One post, way back, suggested they needed to be reset before logging. I mentioned it in a later post, and a subsequent reply said that wasn't necessary! Now, with the latest firmware, every time we flash a tune, the PV asks if we want to reset the fuel trim. But then it says its only necessary if we change anything to do with the air/fuel mixture (or maybe it says VE tables...I can't remember exactly).... Well, isn't that almost every time we flash a tune? What is actually happening when we reset these trims?
You do not have to reset your trims pre-logging run. It just forces the ECM to relearn new values.
Road Warrior
Joined: Aug 2005
Posts: 1,949
Likes: 288
TedMan
Advanced
Joined: May 2011
Posts: 66
Likes: 0
Really? I just ran the cable through the console and zip tied it to the cabling on the neck then up through the plastic gauge housing onto my handlebars. I will probably run it under the tank when I pull the tank to do my handlebars later.
Cruiser
Joined: Jul 2010
Posts: 222
Likes: 1
From: Massachusetts
Remove 5 bolts ( 1 for the seat), disconnect the fuel line which is a quick disconnect and that whole area is opened up for an easy and neat installation.
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
Pass, on your bike, removing the fuel tank is a breeze. A bit more of a headache on an 07 but still not difficult.
Last edited by FX4; Jun 18, 2011 at 10:52 AM.
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Cruiser
Joined: Jan 2011
Posts: 125
Likes: 0
From: Rowlett, TX
The trims are the new learned values... the desired values so to speak. Not every time you flash are you changing the VE tables (it seems like that now since that is what you are tuning). Later on, you may change just your spark, or a temp setting, or enabling something or disabling something. It would not be necessary to reset your trims.
You do not have to reset your trims pre-logging run. It just forces the ECM to relearn new values.
You do not have to reset your trims pre-logging run. It just forces the ECM to relearn new values.
OK...by learned values, you mean the values stored in the adaptive table, that are applied during startup, right? If so, why wouldn't you want to reset these prior to logging? It seems to me that if the ECM applies 'adjustments' to the tune, it's going to change what is measured by the O2 sensors, and so adjustments calculated by logtuner are going to be off as a result. Sure, they'd be right for the tune plus the learned adjustments together, but they would be off if the trims were reset later....
Second question...the guide for the log tuner suggests turning off the adaptive control... Again, assuming that the adaptive control is the where the data in the trims comes from, I guess that means that while my tune has this parameter turned off, this is all a moot point, right?
Finally, when it comes time to reset these trims, when do you do it? If they are applied at startup, then I assume it's a waste of time to do this unless the engine is off, right?
Thanks,
Art
Advanced
Joined: Apr 2010
Posts: 79
Likes: 2
From: Norway
The instructins says that I need to have the stock ECM settings flashed onto the bike prior to using the Power Vision...but I dont have this map since I have been using a Screamin Eagle Pro tuner from the dealer.
How do I get the stock ECM-flash?
Regards,
Kurt
How do I get the stock ECM-flash?
Regards,
Kurt