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99 Explorer O2 Sensor failed

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Old Oct 6, 2004 | 11:02 AM
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Question 99 Explorer O2 Sensor failed

Hi all..

I have a 99 ford explorer 4D, 4WD V6.

I have a Check engin light on that is reporting code 171 - O2 Sensor - Bank 1 is reading to lean..

Can someone point me to where this is located on the truck? The Bank one leads me to believe that there are more than one and I would rather not drop the $60 more than I need to

Thanks for the help
 
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Old Oct 6, 2004 | 02:17 PM
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When I replaced the ones on my '99 XLT there were 4. One on the exhaust pipe before the cat and one after the cat on each side. They look like spark-plugs that are screwed into your exhaust system.
 
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Old Oct 6, 2004 | 02:31 PM
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Originally Posted by Pig Pen Jr
When I replaced the ones on my '99 XLT there were 4. One on the exhaust pipe before the cat and one after the cat on each side. They look like spark-plugs that are screwed into your exhaust system.
I just got off hte horn with my local shop.. They told me that Bank 1 is right before the CAT... But I only have 2, not 4

Thanks for the reply.... Appreicate the help
 
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Old Oct 8, 2004 | 07:24 AM
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# of O2 sensors

I believe that all Explorers thru '99 have 4 sensors. On my '96 with a V6, sensor #1 is located on the passenger side exhaust manifold about halfway between the exhaust header and the converter. Best access is through the wheel well by removing the inner fender skirt. I thought only Rangers with the 2.3L had two sensors?
 
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Old Oct 8, 2004 | 07:31 AM
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Originally Posted by ajguzik
I believe that all Explorers thru '99 have 4 sensors. On my '96 with a V6, sensor #1 is located on the passenger side exhaust manifold about halfway between the exhaust header and the converter. Best access is through the wheel well by removing the inner fender skirt. I thought only Rangers with the 2.3L had two sensors?
I really have no clue.. I am at this point believing the ford guy, after all he should know

I will find out for sure tomorrow when I get down underneath it and see it for my self..
 
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Old Oct 8, 2004 | 08:01 AM
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He probably has the standard 4.0 and not the 4.0 SOHC. That is the only differance I can see it being.
 
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Old Oct 8, 2004 | 08:27 AM
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Originally Posted by Pig Pen Jr
He probably has the standard 4.0 and not the 4.0 SOHC. That is the only differance I can see it being.
Not sure.. I will have to check
 
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Old Oct 9, 2004 | 11:12 AM
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Originally Posted by stunod2002
Not sure.. I will have to check
I actually have the SOHC 4.0
 
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Old Oct 9, 2004 | 01:22 PM
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Originally Posted by ajguzik
I believe that all Explorers thru '99 have 4 sensors. On my '96 with a V6, sensor #1 is located on the passenger side exhaust manifold about halfway between the exhaust header and the converter. Best access is through the wheel well by removing the inner fender skirt. I thought only Rangers with the 2.3L had two sensors?
Well There is infact 4 sensors.. I could not find anything that specifically said what Bank #1 was, however the wonderful techs at AutoZone said that it was the driver side.. SoI gave that a shot.. I cleared error code so not its a wait and see..

Hopefully the AutoZone guys know what they are talking about..

Luckilly that sensor wasn't all that bad so I can change it to the other side if needed..
 
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Old Oct 9, 2004 | 10:17 PM
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I have the ohv standard 4.0, not the sohc.......they all have 4 o2 sensors. banks1 and 2 are before the cats....banks 3 and 4 are after.
 
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