All,
Getting codes about my bank 1 O2 sensor. Heater circuit code and
a code that the sensor had no reading at all.

I had gone nearly 200 miles with a few trips and on the leg of a 45 mile trip - the Check Engine light came on after about 15 minutes with two codes.

So I was reading that "Bank 1" means the side with Cylinder 1.
As I understand it, Cylinder 1 is on the left when you are actually sitting and driving the ROVER.

Or on the RIGHT if you are looking into the engine bay with the hood up.

So, I finally bought a new one. All shiny from Amazon with the proper plug attached for about $64 with shipping.

I crawled under the Rover today and saw the sensor. I followed the wire up
to a complicated clip and plug. Drat.

There is a black piece of metal holding the bottom of the wire out of the plug
into a metal retainer which holds the wire from flopping around.

Above that is the orange plug.

All of this is securely fastened down to this black metal piece. The Orange
plug is way up there.

So, how to unclip this O2 plug from the engine harness dear experts?

Even if you can get one hand up there to reach it...

I would probably "break it" if on my own left to do it.

I had a look at it and said "oh bah".

I better ask the board.
Looks like a long wrench can get the actual O2 sensor out as there is some room for a wrench to go in there.

Of course, after the plug is unclipped. The plug seems to be harder than getting out the actual sensor..

So, I need to buy a wrench. What MM size?
And, deal with that orange plug..

 

I can't recall the size of the the special socket, but it is standard, and if you go to Auto Zone or Advance Auto and ask for an offset oxygen sensor socket, it is standard and will fit.

As for the attachment plug point, these seem to be variable. I had no trouble reaching and unplugging my front sensors; one in the back was impossible to reach as it was way up in the chassis. The work-around is to buy the Bosch O2 sensor with the "universal" wiring plug (or whatever they call it). You basically cut the wires to the original sensor downstream of the original plug, and install a new plug that you can actually access. Of course, make sure you can remove the sensor first, as once you cut the wires, you're committed.

DRW

 

Thanks for the reply...
For the record..
I was able to change the sensor.

1) Unscrewed it with a 22MM long spanner
2) Look at the replacement sensor and see where the push tab is.
3) Reach up to your old sensor plug - push in the push tab using one hand with your thumb and while pulling hard on the wire with the other hand..
Plug should come out.
4) Install the new sensor by threading it in and tightening.
5) Place the new plug up into the old plug. This is the hardest part. Get the new plug to simply "stay" up into the old plug - it is not snapped in yet.
6) Get a screw driver. A long one. Use the blade to press against the plastic - avoid scuffing any wires entering the plug.
7) Press gently until the "click" is heard.
8) You are done installing.
9) Test the O2 operation with a scanner - looking at the live O2 sensors when the engine running. Voltage should oscillate from .1 to .9 volts or so.

 

Breathing some life into this thread because I went searching for some advice on how to get these SOBs out and didn't find much. This pertains to the front passenger o2 sensor--that is, if you're sitting in the Rover, the front right sensor.

For this sensor, I did all of the work from the hood.

First, for those of you, like me, who aren't mechanics, make sure you've got the right sensor. The front sensors are visible and "accessible" from under the hood. You can also see them under the vehicle, but if what you're working on can't be seen from under the hood/bonnet, you're looking at the downstream/back sensors.

Next, PB Blaster the crud out of the sensor. Let it soak for awhile. A lot of folks recommend an overnight soak, I don't think that's a bad idea.

The next step is to unclip the sensor. Folks take different approaches to this, but I found success unclipping the entire connection from its mounting bracket and then disconnecting the o2 sensor plug from its receptacle. Removing the pair from the mounting bracket is tough due to space constraints. What worked for me was using a flat head screwdriver to depress the necessary tab. Before doing that, however, make sure the o2 sensor wire is unclipped from a plastic clip holding it in place.

The tab you need to depress is at the very top of the pair of connectors, on the side facing the front of the vehicle. To be clear, the tab you need to depress to remove the o2 sensor plug and its receptacle from the mounting bracket is not on the o2 sensor plug, it is on the receptacle. Poke around with the flat head a bit to make sure you've got the tab position figured out (a flashlight will help you find things). Once you have the tab depressed, grab another screwdriver, and apply upward pressure from under the coupled pair--from underneath the o2 sensor plug. For me, with very little pressure, the coupled pair slid off the mounting bracket. From there, it's pretty easy to remove the o2 sensor plug from its receptacle.

Next up is unscrewing the o2 sensor. With any luck, the pentrating oil will have done its work. An offset 7/8 socket worked well for me. That plus a 3" extension was what eventually did the trick. Because the socket is offset, you need to fiddle with placement and orientation of your wrench and socket to get some decent leverage. With some effort, it will eventually come out.

Installation is just the reverse.

For me, I spent a lot of time going back and forth from under the vehicle to back in the hood, not sure what way to remove the sensor and unclip it. Perhaps this sensor can be done from underneath, but if you find yourself in the same back-and-forth dance, just know that I did both the unclip and unscrewing from under the bonnet/hood. I specify this, because I think the driver's/left side o2 sensor might be best removed by working underneath the vehicle (but I don't know this yet).

Here's hoping the driver's side is a bit easier for me when I tackle it at some point in the future!

 

You need to get a flashlight or a good trouble light to SEE the connector.

For the record ---
That repair on the O2 Sensor went 10,000 miles with NO ISSUES.

The sensor was a Bosch direct replacement from Amazon.

You need to press a clip to get the plug off of the stay hooked to the chassis.

Then once the plug assy is free, you need to press a different tang to get the sensor un plugged from the harness.

All the while your arms are stretched way out and dirt is falling into your eyes.

 

While the topic is active, can someone tell me if the connector for the passenger side downstream (after cat) o2 sensor is up near the top of the transmission?After we bought the D2 I was underneath and found that the wires were torn out and the connector on the sensor end gone. So I am trying to make sure I know where this one plugs in when I replace it. I see a gray connector that looks like the right one high on the tranny. Thanks.

 

Yes, passenger side downstream was way up by the transfer case as I recall. Not positive if it was a grey plug, but sounds right to me.

Dave

 

i believe orange is the front and gray are for the rear.

 

It's on top of the transfer case, to the right of the front prop shaft (right when sitting at the wheel) on a metal bracket bolted to the top of the t-case, with two other connectors.

 

Thanks for the location confirmations everyone. Wish I had the sensor side of the connector so I could splice the broken wires and see if the sensor is still working okay. Anybody know a source for just the connector or have an old one from a bad sensor laying around? Thanks again for the help.