AFR Gauge question
#5
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This.....in fact now I can't imagine operating without it. It's a great trouble shooting tool on the fly should an issue arise. It offers the ability to discern between electrical and fuel problems. For example, you hear the motor stumble and quit and the AFR rolls to 23+, you know you had a fuel issue (I had this happen when an internal diaphragm failed on a VST pump). If AFR was steady and the motor quits or stumbles it points towards electrical.
#6
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This.....in fact now I can't imagine operating without it. It's a great trouble shooting tool on the fly should an issue arise. It offers the ability to discern between electrical and fuel problems. For example, you hear the motor stumble and quit and the AFR rolls to 23+, you know you had a fuel issue (I had this happen when an internal diaphragm failed on a VST pump). If AFR was steady and the motor quits or stumbles it points towards electrical.
#7
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From: Taunton Ma
I like them as a tuning tool, but really don't have a need for them full time. Fuel pressure dropping will show you the same problem a lean air fuel reading will. It's all just data, it's up to you to interpret it.
#8
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This.....in fact now I can't imagine operating without it. It's a great trouble shooting tool on the fly should an issue arise. It offers the ability to discern between electrical and fuel problems. For example, you hear the motor stumble and quit and the AFR rolls to 23+, you know you had a fuel issue (I had this happen when an internal diaphragm failed on a VST pump). If AFR was steady and the motor quits or stumbles it points towards electrical.
Thanks for the responses.
#9
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From: Michigan
Disclaimer: Always take the time to read your plugs!! more so if the engine has not been run on a dyno first!!
Last edited by abones; 04-23-2016 at 07:56 AM. Reason: added disclaimer
#10
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The problem is watching fuel pressure drop will not tell you HOW lean it got. Did it go from 12.5 t0 13.0? That wouldn't concern me too much. If it went from 12.3 to 15.0 under load now that would be an issue. Wideband will tell you that. Fuel pressure will not.




