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Different AFR readings

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Old Jun 5, 2005 | 06:03 AM
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Default Different AFR readings

I'm trying to tune in SD but, I notice that my lm-1 is giving different readings than what my histogram is.

I'm seeing 12.5 across the entire board on the histogram but the lm-1 seems more accurate with readings around 14.7

I think something is wrong with the histogram but, does anyone have an idea?

Thanks.
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Old Jun 5, 2005 | 06:58 AM
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Now, I can not pull up the LM-1 manager. It says it is searching for the device. Analog out is plugged into the black box and then, ran to the lap top serial port.

If the LM-1 is reading correctly while tuning but, it is not showing up correctly in the histogram, I'm starting to think that my EIO isn't working.
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Old Jun 5, 2005 | 10:37 AM
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thats kinda what im going through.
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Old Jun 5, 2005 | 11:15 AM
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Have you check your table display to make sure you are logging LM-1 Wideband in the correct input cell? It's a simple thing to miss, and the first thing I would check.
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Old Jun 5, 2005 | 11:58 AM
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Originally Posted by txhorns281
Have you check your table display to make sure you are logging LM-1 Wideband in the correct input cell? It's a simple thing to miss, and the first thing I would check.
In the correct input cell? I'm not exactly sure what that means but I have added the LM-1 to the table display.

I'd like to think I've made a simple mistake but, I've used my wideband before and I think I have doubled checked all of my steps. Also, I find it odd that I can not open up the LM-1 manager which uses the EIO box to do so.

I'm pointing fingers at the EIO but, I'm really unsure at this point.

Thanks for your help Texas Horns.
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Old Jun 5, 2005 | 08:07 PM
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Both your black box and Wide band have to share the same ground to the vehicle. If they don't the readings could be off. You'll find more info on the EFI website. Ground it to pin #4.. Is that how you did it?


Last edited by Ripped427; Jun 5, 2005 at 11:47 PM.
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Old Jun 5, 2005 | 10:07 PM
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Originally Posted by SportSide 5.3
In the correct input cell? I'm not exactly sure what that means but I have added the LM-1 to the table display.

I'd like to think I've made a simple mistake but, I've used my wideband before and I think I have doubled checked all of my steps. Also, I find it odd that I can not open up the LM-1 manager which uses the EIO box to do so.

I'm pointing fingers at the EIO but, I'm really unsure at this point.

Thanks for your help Texas Horns.
The bottom 3 rows are designated for the EIO. Some peeps don't know that! Just a thought... You said you can't connect the LM-1 to your laptop either though right? Are you going through a native serial port or USB adapter? Also, I'm sure you have, but check your wire splices too...

Again, just some thoughts... Hoping it's not yer EIO...
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Old Jun 6, 2005 | 06:35 AM
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Gotcha. Correct, it is not getting a reading. The unit is connected thru a USB adapter. Wouldn't work on my desktop either. But like I said, the LM-1 unit is giving correct readings while tuning. Just, it's not showing up correctly on the histogram display.

Thanks for helping me narrow it down. I think I'll be able to figure it out.
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Old Jun 6, 2005 | 02:14 PM
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Originally Posted by SportSide 5.3
Gotcha. Correct, it is not getting a reading. The unit is connected thru a USB adapter. Wouldn't work on my desktop either. But like I said, the LM-1 unit is giving correct readings while tuning. Just, it's not showing up correctly on the histogram display.

Thanks for helping me narrow it down. I think I'll be able to figure it out.
The other thing to remember is that AUX 1 on the LM-1 is setup incorrectly for what your doing. You'll need to program the voltage output on the LM-1 AUX 1 for the proper voltage. If you don't do that you'll get whacky readings that will only be close when its in range.
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Old Jun 6, 2005 | 03:16 PM
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i would assume he hasnt programmed the lm-1...thats what i did at first...read 12.5ish in all cells till i corrected it.
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Old Jun 6, 2005 | 07:49 PM
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Hmmm. Yeah, I corrected it the first time I ran the wideband. But, I had taken it out since then and now I was going to do some more tuning and I was getting the 12.5 readings.

I went to set it up, using the LM-1 manager but I couldn't get the lap top or my desktop computer to recognize it was connected. This is where I ran the lm-1 analog out thru the EIO into the lap by USB. It's possible the analog out cable is acting funny. I might try and rig up a 3.5mm stereo wire like I've seen mentioned here before.

Thanks for your help guys.
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