Again, thanks Jamie. I understand that it is a closed loop and it would not respond well when the sensors are working outside their operational range on the 'rich' side. By PID I'm assuming you're referring to a Proportional-Integral-Derivative controller which makes sense in this application. My question was, when I'm running my '08 in closed loop, with CLB set to 750, what is the target AFR? Interpolation from your graph shows about 14.2:1 AFR but the scale is pretty crude for any precision. I was just curious as a reference when I start tweaking my AFR table in open loop.

 

What I have to do if the ET reach to 300*F in normal trafic, I thinking of add some more fuel to global fuel of PV feature but not sure it can fix the problem.Pls help !!!

 

CLB of 750mv is going to be approx 14.3 AFR

 

See the following chart:

http://harley.uk.net/doku.php?id=tec...ing#o2_sensors

 

Well, this chart is completely contradictory to the one carbonfiberwingnut posted a few pages back. Not just in exact voltages but in the direction the voltages go...ie the previous chart shows that low voltage means rich but this one shows lower voltage means lean. And if this table is correct, then what I've been getting on my sensors is actually probably close to correct.

I posted the other table below for reference. It is clearly wrong for our sensors.

 

Your chart is 0-5V which would be typical for a Wideband sensor most likely an aftermarket application, with a chart like this you would need to know the specific wideband controller and sensor it is referring to. This chart would not apply to any HD.

Narrowband O2 sensors are 0-1V, also note many HD applications also have a voltage offset which is applied as well. This includes all models with 12mm heated sensors as well as 08-09 FLH models. To work out the math you need to know this offset.

 

Which has me totally baffled, My O2 Voltages in my logs average in the 1.6, +/- .2 in the closed loop portion of my tune.?

I don't have CLB, I have CLLR.

 

Red,

Sorry for any confusion this may have caused. I run a wide band system.. I don't have any experience with the narrow band. It wasn't until Jamie posted the chart showing they are "Basically" ON or OFF hence the Narrow band that it dawned on me you're having issues on a newer set up and that you probably have Narrow Band? The one thing I wasn't clear on was the voltages and really posted the Lambda chart so you could bounce Lambda's off your AFR. The Lambda and the AFR still hold true, but the voltages if narrow band are not only NOT close, but not even in the same universe, add to that the Apples and Oranges difference between Narrow vs Wide, and I may have had you chasing your tail. I hope that is not the case, if so sorry about that.

How are you coming along in getting fixed?

 

No worries, I feel much better now. I am definitely using the newer 12mm narrow band sensors my '13 came with. Now that I know the voltages that are showing on the PV sorta make sense I'm gonna reconsider. However, the problem still exists....that autotuning still leans out my VEs way too much for logic. There's simply no explanation for ending up with 10-15% leaner cells than the base tune that was designed for my setup. I may still spend $100 to replace both sensors, if for nothing more than diagnostic purposes.

 

I assume you mean during engine operation. Because when I stop the engine, the voltages slowly rise to 5V.