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AFR crazy reading, something wrong?

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Old Sep 27, 2005 | 11:00 PM
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Default AFR crazy reading, something wrong?

hooked my wb up leaving narrow band hanging but still connected.

at idle im getting around 14.0 afr but as soon as i take off it goes way high like over 22.0 AFR and if i go wot it goes down to about 8.00 afr never really any where near 14.7.

Think the engine is really running that lean or rich? I see no signs like black smoke or the engine feeling real weak or any knocking. EFIlive and logworks were showing the same numbers.

I'm running custom os number 3 efilive using the afr to lean out but at the most im only commanding 15.9 in the cruise area other spots are at 14.63 which is factory for a truck. it is in semi loop

What gives?

maybe exhause leak?
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Old Sep 27, 2005 | 11:09 PM
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if its an lc-1 i had similar problem. do a full heater calibration.
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Old Sep 27, 2005 | 11:11 PM
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yup its a lc-1 i will do that again, i was like wtf
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Old Sep 27, 2005 | 11:32 PM
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Sounds like it needs recalibrating.
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Old Sep 27, 2005 | 11:45 PM
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you cannot have a stock front sensor plugged in and hanging in free air. You will have problems.

if you need to use the front sensor bung, put the vehicle into open loop
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Old Sep 27, 2005 | 11:58 PM
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Originally Posted by slow
you cannot have a stock front sensor plugged in and hanging in free air. You will have problems.

if you need to use the front sensor bung, put the vehicle into open loop
mostly is in open loop with the custom os, only time really in closed loop is at certain idle points other than that it is open loop
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Old Sep 28, 2005 | 01:59 AM
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my lc1 was freaked out until i got the free air cal down right. now it is very happy
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Old Sep 28, 2005 | 08:15 AM
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Originally Posted by SS2win
my lc1 was freaked out until i got the free air cal down right. now it is very happy

how many times it take you to free cal and any suggestions or tips on doing it? I followed instructions on manuel
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Old Sep 28, 2005 | 07:17 PM
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Did you use the LED light and the grounding momentary push button switch?

Mine worked just as you described the first time, but after the second calib, has worked flawlessly.
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Old Sep 28, 2005 | 10:28 PM
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At first mine was very flakey and I thought I would have to send it back. Once I ran the car for a while it settled in.

Doing a Free Air calibration requires you to disconnect the sensor for 10 seconds but if you can hook up the serial bus to your laptop and run the "LM Programmer" under the tools submenu, there is a reset button that will set the device to defaults without having to physically disconnect the sensor.

So what I do is let the car sit for 12 hours or better so the air in the exhaust pipe is "free" of exhaust gases (prolly better to remove the sensor but that's lots of work). Turn on the ignition, reset the sensor as described above, the LED will blink steady, keep ignition on for 2-3 minutes to be sure the free air cal takes, then turn it off. wait 10 seconds or so and turn it on (don't start engine - obvious, right?) and hit the reset button. Wait for the LED to warmup and go solid, then turn off again. Now hit the ignition, crank it up and let the engine warm up to operating temp before you start logging.

BTW: if you still have the air pump hooked up the WB will show 17-20:1 while it is running. it will cut off after 190 seconds or so and you'll see normal AFR readings...

let me know how this works for you
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Old Sep 29, 2005 | 03:23 AM
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I guess this is where the Innovate XD-1 Guage comes in real handy. It calibrates the gauge and can't mess it up.
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