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O2 Sensor problems, Help Please.

jese_007

New Member
Joined
December 23, 2008
Messages
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City, State
vacaville,ca
Year, Model & Trim Level
1998 explorer 4.0L vin x
Hello, I am having o2 sensor issues, and am looking for some suggestions.

I have 1998 explorer 4.0L VIN X, Ohv 4x4. I have a Craftsman obdii scanner with live data capability. All of the O2 Sensors are brand new. All systems checks are complete with no codes. In live data mode all of the O2 sensors are -100% and 0 voltage. Took it to smog in california and it failed. High emissions at idle. everything else passed. visual, functional, evap. I am looking for pinout diagram so I can test wire continuity. Also, All o2 sensors were working properly with green light for emissions on scanner. Then they all stopped working at the same time. Any Ideas and suggestions would be awesome.
 


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corkey

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Location
Sioux Narrows Canada
City, State
Elite Canuck,multiple ifs offender,, and musky maniac,, i wheel and i fish,,
Year, Model & Trim Level
99 xls,96 xl,91,08 Ranger
moved this thread to the 95-2001 section so it could be seen by more people,,

Welcome to the forum,,
 




jese_007

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City, State
vacaville,ca
Year, Model & Trim Level
1998 explorer 4.0L vin x
you already moved it for me? Thanks! Im new to this, so I appreciate it
 




rb142

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Detroit, MI
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2001 Ranger XLT 4X4
There's something very strange going on there. Look for something that would affect them all, like a power or ground issue, broken wires or a bad connection in a common wire harness, etc. Try to find a wiring diagram. That will help a lot.
 




jese_007

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December 23, 2008
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City, State
vacaville,ca
Year, Model & Trim Level
1998 explorer 4.0L vin x
Do you have any Ideas where I might find a wiring diagram or a pin out diagram. Ive seen the ones for the SOHC 4.0L, but I haven't seen any for the OHV 4.0L.
 




bobflood

Elite Explorer
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City, State
Powder Springs, GA
Year, Model & Trim Level
1997 Eddie Bauer V8 2WD
Great source for wiring diagrams:
Auto - Online Repair Info
http://search.ebscohost.com/
Login ID: rrcc
Login PW: rebsco
Select: Auto Repair Reference Center
Fill in: Find Your Vehicle
Follow prompts down to Wiring Diagrams.
 




1992fordgreen

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City, State
Inside the Rehabilitation Center
Year, Model & Trim Level
95 SC400 92 SC400 96 Ex
Are you sure you got the correct o2 sensors? Happened to me before lol
 




jese_007

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City, State
vacaville,ca
Year, Model & Trim Level
1998 explorer 4.0L vin x
I got the ones the autoparts gave me
 




Turdle

Lowrider
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2000 Mounty




Runnin'OnEmpty

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2000 Sport
......Also, All o2 sensors were working properly with green light for emissions on scanner. Then they all stopped working at the same time. Any Ideas and suggestions would be awesome.
Maybe a blown fuse to the sensors? If a fuse is blown,
look for a sensor wire shorting out somewhere, possibly
on a header pipe. The aft-cat sensor wire routes directly
above the cat, and can fall onto the cat and burn, so
check that one specifically.
 




Nathan2004

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March 4, 2014
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City, State
Willmar, MN
Year, Model & Trim Level
1998 Ford Explorer XLT
I have the exact same problem on my 1998 explorer xlt 4.0 sohc. All plugs and wires have been replaced and all 4 oxygen sensors were replaced but the fuel trims are all at -100% and there is 0v from the sensors. I have a scan tool so i can check codes and readings. Fuse 13 is good along with all the other fuses. There is no check engine light on and no codes stored. engine runs fine but has a tick noise. And it gets terrible gas mileage. Any ides I did not see any of the wires touching anything or broken.
 




nordictom

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City, State
Surf City, CA
Year, Model & Trim Level
1998 Explorer 4x4
Any update on the repair progress???????


NT
 




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