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Discussion Starter #1
Alright, here's the deal. Installed LT header (catless OBX) Did all the part throttle stuff and right now when I log, I see the STFTs all at 0 to -2... I installed a PLX DM-6 with the Bosch WB sensor and it reads 16.3 through 17 normal driving... When I do go WOT it comes down to 14.7 to 15.5... WAY TOO LEAN! I turned on LTFTs just to see where they were nd they were at +7... If I go into HP tuners and force open loop my WB does not change! AT ALL!!! I've tested the sensor according to the PLX install instructions... all seems good there... I've checked the ground on the unit and verified power is at 12.8V... Any suggestions? Is my car really running that lean? Is there a problem with the WB sensor?
 

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Are you reading the wideband reading in HPT or plx software?
 

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Discussion Starter #3
I have the PLX set up to push the 0-5V out to HPTuners... HPTuners sees the PLX output and it matches what the PLX gauge is reading... if that makes sense..
 

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Makes perfect sense. Any chance you have an exhaust leak pre wideband sensor? Does.that wideband.have a free air calibration?
 

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Discussion Starter #5
The exhaust is really tight all the way up to the block! Had the car running on the lift and I was all over underneath it.
If you expose the wideband to the air and turn it on it will read AIR in about 23 seconds... it is not a required calibration...and did not change the reading once that was done...
Did that yesterday and then again this morning.. I'm going to contact PLX in the afternoon tomorrow... see if they have any ideas...
 

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Did you get the PLX DM6/AFR combo? Or did you source your own wideband and then put the DM6 head on it?
 

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Yea, if it's off, a quick call to them will hopefully help. If it's accurate, time to update the tune. Are you at stock tune ? I don't see any mods in your sig so are you even cortex tuned, or 100% stock?
 

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Discussion Starter #9
HP tuners... only tune so far is just tuning the part throttle bit... STFTs are all reading 0 to -2... and then I have messed with the tranny a little bit...
 

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Discussion Starter #10
Hey mtocrs1 and Zep... Think I got this figured out... Turns out it is probably a bad sensor module... Should be sending 9V to the WB O2 sensor and it sending a straight 12V... which causes the WB to read leaner than it actually is... PLX was great to work with on the phone and they were able to narrow this down pretty quick. Bad part is that I have to ship the sending unit to CA for them to fix or replace and then they will send it back... So I am without the WB for a couple of weeks... Just more time to jump on the G8Board and HPTuners forums and do some more reading! Thanks for the help and suggestions!
 

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Note: If you will be "without the wideband for a few weeks" make sure to REMOVE the wideband from your exhaust and put a bung plug in (may have been included with the kit? Or any good exhaust shop should be able to thread one in there in the meantime for you for a couple of bucks)

Without the wideband sensor having power to it, it can damage the tip, which will cause you further problems down the road. Remove it till you get everything fixed/replaced, then have it reinstalled when you've powered it back up and are ready to test.

Great to hear that you had great success with PLX support, I've called them a few times myself and have nothing but great things to say about them!

What I love is how you can daisy chain the sensors together... one of my previous projects was documented in a youtube video of the triple DM-6's in a 1974 cuda, and this is proof that their support subsystem is top notch! :D
 

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Discussion Starter #12
Zep... O2 sensor is already in a baggie in the toolbox and yeah I have a bung plug in its place! Was looking into the DM-100 as a scan gauge and another DM-6 for other parameters... Now just need somebody to donate the triple gauge stack!
I'm gonna check out that Cuda video! Also sent you a PM on Facebook... it's probably in your other folder!

Jimmy
 

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If your trims are slightly negative then flatline the PE table at 1.20 in all cells. Change PE delay RPM to 0 and Enrichment rate to 1.0

That should get you around 12.0-12.2:1 A/F ratio on the street. I suggest 24 degrees timing at WOT to avoid spark knock and hopefully you put a set of NGK TR6 plugs in the car when you installed the headers :)
 
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