Check engine light
#1
#2
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O2s will come and go. I've reset one a dozen times over 3 years and it is still working 99.5% of the time. The sensor doesn't necessarily fail... as in stop... it just starts sending wrong readings, thus tripping the Check Engine Light CEL. Buildup on it, etc usually is the leading factor.
it is not a hard job to replace. Just figure out which one it is. Some Ds have 2 O2s and some have 4. Ouch!
IndyDurango
it is not a hard job to replace. Just figure out which one it is. Some Ds have 2 O2s and some have 4. Ouch!
IndyDurango
#3
#5
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I seem to remember reading somewhere.........oh yeah!! It was this forum........that the 4.7 has 4 sensors, 2 per bank one before the cat converter (UPSTREAM) and one aft of the converter (DOWNSTREAM) the two upstream converters are the ones that are used for emissions, and the downstream ones are basically back up.
+2 Indy on checking which sensor. I would guess that if you had a just sensor fail code, see if there is anything to indicate UPSTREAM or DOWNSTREAM. There is a 1 in 4 chance but I would venture to say that if it comes up with a hard code, then I would probably guess the UPSTREAM sensors first, since that should have most of the buildup on them.
+2 Indy on checking which sensor. I would guess that if you had a just sensor fail code, see if there is anything to indicate UPSTREAM or DOWNSTREAM. There is a 1 in 4 chance but I would venture to say that if it comes up with a hard code, then I would probably guess the UPSTREAM sensors first, since that should have most of the buildup on them.