Wide Band O2 sensor response to missfire
Wide Band O2 sensor response to missfire
(OP)
In another site we have a debate going on about a miss fire where a rich mixture suddenly shows lean on a wide band as it loses power for a short interval then shows rich again as it regains power.
This is during a dyno tune on a Honda with a roots blower.
They are trying to decide if it is momentary spark breakdown or a hiccup in the fuel map. The map shows no abnormalities on the laptop.
Does completely unburned fuel show rich or lean on a wide band oxygen sensor.
This is during a dyno tune on a Honda with a roots blower.
They are trying to decide if it is momentary spark breakdown or a hiccup in the fuel map. The map shows no abnormalities on the laptop.
Does completely unburned fuel show rich or lean on a wide band oxygen sensor.
Regards
Pat
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RE: Wide Band O2 sensor response to missfire
Since an O2 sensor is essentially comparing the amount of O2 on two sides of a diaphragm (one side in the exhaust stream, the other in the outside environment), you could theoretically shove a baby down the tailpipe and it wouldn't effect the sensor's reading. Bring in a bunch of air, squirt fuel into it, but forget to ignite the fuel, the O2 ratio is going to look (nearly) like 1:1...
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Wide Band O2 sensor response to missfire
OK, I didn't think I was going to smile all day -- so thanks for turning it around!!
By the way, Pat, I agree that it'll momentarily spike up showing really lean if you don't use any of the oxygen because of a misfire. The sensor responds really fast, but I'm not sure how the engine controller will handle it.
Good on y'all,
Goober Dave
RE: Wide Band O2 sensor response to missfire
Both guys are correct, the reading will show a lean spike.
MS
RE: Wide Band O2 sensor response to missfire
Regards
Pat
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