Code 172 (Running) - lean but no MIL/CEL
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Code 172 (Running) - lean but no MIL/CEL
ok, here is where my 92 stands after warming up the sensors and pulling my codes:
koeo test = 111 (system pass)
continuous code = 172 (lean condition stored in memory)
running test = 172 (is lean now)
here is what is strange to me...there is no MIL/CEL. the bulb is good as i see it on start up, but it doesn't light up during the driving cycle.
the whole reason for pulling my codes was that i saw the MIL light come on while cruising the highway at 60mph. it stayed on for about 10 seconds, then went out. it has done this behavior twice in the last 6 moths or so. very random and not at all common.
so what do you think? is it really running lean during driving (thus in an open loop fuel control?)
i have always assumed if the o2 sensor was detecting a lean condition that it will throw the MIL/CEL...is this right?
koeo test = 111 (system pass)
continuous code = 172 (lean condition stored in memory)
running test = 172 (is lean now)
here is what is strange to me...there is no MIL/CEL. the bulb is good as i see it on start up, but it doesn't light up during the driving cycle.
the whole reason for pulling my codes was that i saw the MIL light come on while cruising the highway at 60mph. it stayed on for about 10 seconds, then went out. it has done this behavior twice in the last 6 moths or so. very random and not at all common.
so what do you think? is it really running lean during driving (thus in an open loop fuel control?)
i have always assumed if the o2 sensor was detecting a lean condition that it will throw the MIL/CEL...is this right?
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Joined: Sep 2002
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From: Gateway to the West
The symptoms must generate the code 40 consecutive times during engine operation for the light to remain lit. Otherwise the light only illuminates when the fault is detected. Once the code has been generated during 40 consecutive engine operating periods, the code will be stored and the light should stay lit. IF the condition exists during the KOER test, the code will show up. My guess is you have caught the problem early.
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huh
so i guess that during my running test it may run lean...but maybe once it gets moving up and down the rpm range during driving, it may not be running lean. thus never turning on the MIL.
i think i would rather have a full out problem than catching one early that isn't consistent enough. well i will search for anything out of wack just as a precaution.
thanks and if anyone else has any insight/advice, please chime in.
i think i would rather have a full out problem than catching one early that isn't consistent enough. well i will search for anything out of wack just as a precaution.
thanks and if anyone else has any insight/advice, please chime in.
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