NGK AFX Wideband reading high vs. HP Tuners

[smokinram]

Hello All,

I am very new to HP Tuners so please bear with me.

Just hooked up a new NGK AFX Wideband to my Procharged 02 LS1 Trans Am and I used the HP Tuners default selection for adding the NGK Wideband to my Hp Tuners Scanner and I am noticing that the readout on the NGK is reading roughly 2.0 to 2.5 higher than what I see on the VCM Scanner.

Any input is greatly appreciated. I don't know weather to go by whats on the gauge or on the scanner now.

Also has anyone bought one of these NGK AFX Widebands lately? The lastest version has a "Mode" button on the front instead of the dial that they used to have. I have not been able to calibrate mine with the mode button. It says to power it up, hold the mode button more than 3 seconds and the screen will read "-CAL_". I am unable to get this to happen. Maybe this is my issue.
Thoughts?

Thanks,
Andy

[IJ.]

Doing the CAL procedure in free air?

Have you checked for voltage offset between what the AFX is out putting and what HP Tuners is reporting in the Laptop?

[smokinram]

Doing the CAL procedure in free air?

Have you checked for voltage offset between what the AFX is out putting and what HP Tuners is reporting in the Laptop?

No I have not. Can you explain how to do this?
When setting up the AFX I just chose it off the list of widebands in HP Tuners. Didn't adjust any parameters.

[IJ.]

Here's a good thread on the subject>>

http://www.hptuners.com/forum/showth...voltage+offset

[smokinram]

Under the "Aux Input List" there is a selection for "Wide band O2 - NGK (afr)".
That is what I have mine set to.
How can I see what offset this predetermined setting is set at?

Looking on HP Tuners website, it says to set up an NGK AFX like this:
Wide Band O2 - NGK: result = volts / 0.7142 + 9

Am I wrong in assuming that their predefined selection for the NGK AFX is different than this?

Sorry if I sound confusing. Just trying to figure this all out. Can't imagine a Wideband gauge is this difficult to make accurate.

Thanks
Andy

[IJ.]

You need to actually measure what's coming out of the NGK and compare it to what HPT reports in the software then adjust the formula based on what your hardware is doing.

Did you read the thread I linked?

[smokinram]

Yes I did read the thread. Still somewhat confusing to me.

[IJ.]

Do you have a multimeter?

[smokinram]

I sure do. Please explain...

[IJ.]

Set it to v DC, Key on Engine off with the Scanner running, probe the green plug where your NGK is wired to the HPT Dongle, now see what voltage is showing in the HPT Scanner for the connected input, that's your voltage offset.

[smokinram]

Where would I see the voltage in the HPT Scanner? I see where it reads AFR, but not voltage.

Do you have an example of what a typical voltage offset may be and the formula to make it work?

[IJ.]

Been awhile since I've used my HPT but from memory it's on the chart display at the bottom on EIO# whatever you plugged it into.

I'd have to dig out my old laptop to get what I did, mine was .24v offset, I tweaked the formula you posted above to get it closer, but having said that it wasn't NOT a linear .24 out.

[gottogo]

You might also try this How To.

http://www.thetuningschool.com/downl...p_wideband.pdf

[IJ.]

And all this is dependant on a correct free air calibration to begin with

Dug the old lappy out (XP machine so past it's useby date)

I have mine set up as 10.66 = 0.618 based on my .24v offset

[Kyne]

I've been having a voltage drop issue with mine as well, never was a problem before and I want to find the problem and not add to the offset. Can you check the voltage at the green connector plugged in and unplugged from hpt and see if it drops voltage only when plugged in.