Calibrate AFR table did something bad

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Jamesl
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Calibrate AFR table did something bad

Post by Jamesl »

I've been trying to use Tuner Studio Analyze Live and I keep getting O2 out of range. Doing some reading I saw where you could use the Calibrate AFR tool to specify your 02 sensor and I thought that might help. I have an ancient LC1. It had been giving me reasonable readings, typically in the range of 12-15 for the past couple weeks of tuning. When I used the Calibrate AFR tool, specifying Lc1-Lc2 (default), the O2 sensor started reading 20+ full lean no matter what I've done. I did a restore to previous msq from a few days ago, and that didn't help. I went in and recalibrated the Lc1 to insure it was set to 0v = 7.35:1 AFR, and 5v=22.39 AFR. Again, no help.

What would cause this weird behavior? How do I get back to where I was?? :cry:
afr screen shot.jpg
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LT401Vette
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Re: Calibrate AFR table did something bad

Post by LT401Vette »

Do you have any idea what your LC-1 is calibrated to output?
It used to be common to have them set up for 10:1-20:1 0-5v, but also 1V-2V was sometimes used.
The 1V-2V would lively make it read very lean with a normal default LC1 cal on the MegaSquirt.

When is the last time you calibrated the O2 on your MegaSquirt? Any idea what it was calibrated for?
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Jamesl
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Re: Calibrate AFR table did something bad

Post by Jamesl »

As I mentioned in my post, the Lc1 is programmed to 0v = 7.35:1 AFR, and 5v=22.39 AFR, which is the factory default for wideband on output 2 of the LC1. I did a clear air calibration of the sensor itself a few weeks ago.

I'm thinking this has to be a software glitch, but certainly could be wrong...
"87 Mr2
'96 Rav4
'65 Econoline Pickup
'75 Super Beetle
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Why? Because I can... :D
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Re: Calibrate AFR table did something bad

Post by jsmcortina »

Enable the "Exhaust gas Volts" gauge on your dash too (right-click on a gauge) and see what that is showing. This should help you determine whether the wideband is sending out the wrong voltage or whether the ECU is interpreting it incorrectly.

James
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Jamesl
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Re: Calibrate AFR table did something bad

Post by Jamesl »

Thanks, James, I didn't know that was an option. I will give it a try.

Note: "Exhaust Gas Oxygen1 - egoVGauge" on the 3.0.18 version of Tuner Studio.
"87 Mr2
'96 Rav4
'65 Econoline Pickup
'75 Super Beetle
All Turbo, all the time
Why? Because I can... :D
Jamesl
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Posts: 239
Joined: Tue Aug 03, 2004 1:52 pm
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Re: Calibrate AFR table did something bad

Post by Jamesl »

In the magical world of computer stuff, the problem resolved itself overnight. I have no clue why. :? I did put up both the afr1Gauge and the egoVGauge side by side and they both responded just as they should.
"87 Mr2
'96 Rav4
'65 Econoline Pickup
'75 Super Beetle
All Turbo, all the time
Why? Because I can... :D
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