I have a 2003 dakota 3.9 4wd. The passenger side upstream 02 sensor needs to be replaced. any clues on how to get at it. cant get to it from up top cant even get my big hands in there to un plug it from under it. can get a socket on it but no way will i be able to get leverage on it. Any one ever take the inner fender liner off to get to it, looks like the only way.

 

Go find Odo the security cheif and shapeshifter I bet he could get in thier and remove it.



Just a bit of fun... I have no idea how you will get it removed???

 

When I did mine I put an O2 sensor socket on it and used the round end of a long handled wrench on it so the handle of the wrench was pointing down. It also helps to spray the sensor with PB Blaster 3 or 4 times during the day and night before you go to replace the sensor. Unplug the sensor and let its wire harness hang down, it is a lot easier to use a wrench on the hex head end of the O2 socket that way. You just need to loosen it up some, then you can turn it out by hand.

As for the wiring, I just removed my air hat, snorkel and air intake box and reached down between the AC rceiver-drier and the distributor. The plug was right there, not too hard to get disconnected, but not exactly easy either. Maybe ask a buddy with smaller hands if you can't get at it yourself. Wiith the connector plug, be sure to slide the red locking tab out of the way first. Also be sure to zip-tie the plug and wiring harness securely to the main wire harness on the firewall. Mine came loose not long ago and the plastic plug connection kept slapping and thumping against the firewall, it made a real loud annoying racket and it took me forever to figure out where the noise was coming from.

Jimmy

 

up stream o2 sensor where is it its not in exhaust pipe or either manifold or crossover????? 1997 3.9l v six...




thanks Willie

 

Willie,

Depending on your truck it may have 1 or 2 upstream O2's, and 1 or 2 downstream (4 total).

California and Canadian trucks have 4 for sure, but some others will aswell.

I know on my Canadian model both upstream O2's are located just above the cat on both side of the vehicle, and just above the sensors are the driver and passenger exhaust manifolds.

Follow the exhaust manifolds down to the cats and you should see the O2's there. It also helps to remove the driver/passenger inner fenders (few plastic clips).