How do you unplug the Bank 2 O2 sensor plug?

[unioncreek]

I have a 98 Explorer 40. SOHC and need to replace the bank 2 O2 sensor. The connector is between the firewall and engine with very little room. So anyone have suggestions?

Bob

 

[J_C]

Would it be easier to access with the wheel and wheel well liner out? Maybe not, I'd look at it before pulling those.

If you look at a pic of the sensor pigtail you will see it has a springy plastic tab. You'd use a pick or small screwdriver pushed into the mating harness connector to it to depress that tab, slide it in parallel to the length of the connector body. If you have a good visual angle for it, you can also come at it from the side at a 90' angle to the connector to push the tab down, whatever allows you to still grasp both connector halves to pull it apart while the latching clip is depressed, but often coming in parallel to it from the side with a small tool, the tool may stay in place so you can let go of the tool to pull the halves apart.

It will be gentler on the plastic if it is not cold. If it's all you can do to warm it, you could cup your hand around it to get it above freezing. If it breaks the sensor end it's no problem because you're replacing it. If it breaks the other end, Rock Auto sells those you can solder-graft (or crimp if you have the appropriate crimp tool) on. Due to the location, if you have to replace it make sure the junction is water tight.

There are more pics of the sensor and harness connectors on Rock Auto.
1998 FORD EXPLORER 4.0L V6 SOHC Oxygen (O2) Sensor | RockAuto

 

[unioncreek]

I quickly peeked in under the fender liner and it looks like that would be easier. If I have time tomorrow I'll try it.

 

[imp]

There are more pics of the sensor and harness connectors on Rock Auto.
1998 FORD EXPLORER 4.0L V6 SOHC Oxygen (O2) Sensor | RockAuto

View attachment 175998

@J_C Please note that the aftermarket sensor connector lacks the orienting lugs of the original, which allows the one shown to plug into ETHER front or rear position (there are 2 sensors, NOT alike). The lugs were excluded to allow servicing of non-Ford vehicles with that same sensor. Below is the harness (female) connector showing the 2 grooves into which the lugs on OEM sensors align themselves.

Connector below lacks the aligning keys.......

 

[410Fortune]

Some of the sensors are a pita, you either bear hug the transmission and unclip them one handed and clip them back in with one hand while praying, or go through the wheel well. When those fail you can always pull the seats and center console, get access through the floor (on the v8 trucks 3 of the sensors are plugged in here)