AFR for U7191

[evadllig]

Mike,

I have a Trailblazer SS 2006 2wd and I have a Diablo U7191. I do have a K&N Aircharger and a Corsa Touring Catback.

I have have been reading 06MonteSS write up on beginners tuning and I have been doing some monitoring of the AFR with the Diablo. When I first start up the truck the AFR moves up and down as I drive but very soon (it would seem after I am out of the closed loop operation) the AFR locks in on 14.75 and does not move at all after that.

Is this the "known bug" the 06MonteSS was talking about?

Also during that short time when the AFR was moving I did a WOT blast and the number shot up to 18.xx. Is this because the truck was in open loop or am I running that lean? Or should I do an actual log to see the real AFR?

Thanks
Dave

PS I plan on doing all of my adjustments to the tune after the TCM update comes out. I want to do this only once.

[mikel]

There is an issue with the inferred A/F readout, but not what you described....
The ratio should be 14.7:1 anytime except at WOT.
The bug is when you go WOT, it is invering the parameter.
The latest version of the Dataviewer will display this properly if you choose to view the logs on the PC.

Thanks

[06MonteSS]

first... after first starting up, the AFR is adjusting as the vehicle (O2's) are warming up. normal. You don't really want to log anything until after about 15 minutes of driving, so that everything is up to normal operating temps. 14.75 is the normal (stoich) AFR for normal driving/cruising and won't change. The ECM constantly adjust the fueling to keep it at this ratio. again - normal.

second - no, this is not the bug I was talking about.

third - THIS is the bug I was talking about. On the screen, the Predator shows the AFR at WOT incorrectly, but it IS correct in the saved log.

fourth - p.s. -- HA HA HA HA HA, do it just once - that's a good one! HA HA HA HA When it comes to doing the actual fine tuning, you're gonna have to install the diablo tune, then do a log. analyze the data in the log, and make adjustments to the injector slope and PE fueling. then you'll have to drive for about 30 miles to let the injector change and ltft's settle in at the new setting - then do another log. Then you'll need to make another round of changes to fine tune it some more.

not to worry, we'll getcha there!




p.s. Mike - DAMN! you didn't type as much so you beat me to it!

[FastBlueSS]

How much longer till TCM support?

[evadllig]

Thanks Guys

Clears alot up for me...

PS - your right I am sure I will be making many fine tuning adjustment

[jimmybuckets]

Ha! TCM support!