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Old 02-18-2009, 05:52 PM   #1
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Default Noisy AFR?

I think I may have some noise in my O2 signal. I never thought much of it, just assumed it was normal until I went to tune a snowmobile and it completely tuned the VE table in about 5 iterations (mine takes hundreds) and the O2 reading was very smooth.

Is this what the O2 signal is supposed to look like or do I need to go do some investigation regarding my grounds?
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Old 02-18-2009, 05:57 PM   #2
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My AFR reading is noisier than that. I need to fix it one day. It's a grounding/power supply problem in my case.
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Old 02-18-2009, 07:18 PM   #3
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Mine looks about like that, with little ups & downs of +/- .1-.2, so I'd say it's pretty normal. I've often heard that the LC-1 is faster than other widebands (I've not personally used any others for comparison) and a higher sampling rate is going to let you see every little fluctuation. Do you have the same model WBO2 in the Miata as was used for the snowmobile? One with a lower refresh rate would steamroller over lots of those little blips and give you a smoother looking AFR line. The type of engine you're tuning probably contributes as well.
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Old 02-19-2009, 01:18 AM   #4
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Quote:
Originally Posted by ScottFW View Post
Do you have the same model WBO2 in the Miata as was used for the snowmobile? One with a lower refresh rate would steamroller over lots of those little blips and give you a smoother looking AFR line. The type of engine you're tuning probably contributes as well.
No, not the same model. The one in the snowmobile is a generic brand one and it would make sense that it's a much slower unit. I still don't understand why my VE table took so long to tune but the snowmobile can tune a complete table (from a manually generated table that barely runs) in literally 5 iterations.
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