It certainly would be very helpful if posters would state at the beginning of their post the year and model of the car they are presenting. Most of the posts I have looked at have different configurations of wires, hoses, heat shields, etc than mine and others and so may not work on every car.

My car is a model year 2001 XKR white convertible built in June 2000. The code is P1646. Both the gold and silver circuits in the right A bank upstream sensor read zero ohms. The replacement Bosch 15627 sensor (for 2001) measures zero and 8 ohms so apparently the old sensor is bad. The sensors for other years and other models seem to have different ohm readings and different part numbers.

I have looked at all the threads in this forum I could find about the upper O2 sensors.
The lower O2 sensors were easy to get using the many extensions and ratchet torque wrench behind the transmission method. I was surprised at how much force was required to break them loose.
My right side has a fiberglass heat shield above the upper sensor that would have to be destroyed to remove. The left side has a metal one that’s a *itch.

While going through all the posts I ran across (I think it was Gus) someone using an air hammer to crack loose the upper O2 sensors in a XKR. Would whoever did that please tell in detail how they did it? (Tools used and how – part number if possible, length of air hammer bit, etc)

I am having troubles with the upstreams. I can see them and even barely get my hand on them but don’t have enough wrench swing room to loosen them. They are extremely tight. Once I cracked the downstream ones loose I could turn them out with my fingers but I can’t get the upstreamers to crack loose.

Finally got an O2 socket on the right side upper sensor from underneath using many extensions and a universal joint with the behind the transmission method similar to the lower sensor removal. Used a long ratchet torque wrench with a pipe extension to about 2.5 feet and could not break it loose even after sloshing everything liberally with PB Blaster. I have an AirCat 1150 impact wrench with about 900 ft lbs removal torque which I am considering using but I am afraid if it breaks something (u-joint, socket, etc) it will flail around and smash other tubing etc before I can stop it. Has anyone used an impact wrench to remove these sensors?

Does anyone really know how the Jaguar dealer mechanics do this? The Jag dealer I called said about 3 hours ($150-$180) for labor and $359 for 1 sensor. I bought the Bosch sensor from Amazon for $83 and a local mechanic who specializes in Jags said same price for labor if I bring the sensor.

I have tried the AC holes in the firewall thing. Had to remove the center console to move the carpet as it was solidly secured. Thanks to the following videos it was easy. Just be sure you can get the shift lever out of park as you do this job.
This shows how to remove the console: This shows how to remove the J-gate trim piece: When pushing the extension bar through the right side hole it runs in to a “loom” of 4 “rubber” tubes and the clamp holding them together which is fastened to the heat shield. This group of tubes is not mentioned or shown in any other threads. It would require really bending them a lot with a lot of force to get them enough out of the way to get any combination of sockets, u-joints, etc on the sensor. With all the problems of leaking hoses and tubes for the various functions in these cars I am afraid to do that because only God knows where these tubes go to or come from or what function they serve and how I could possibly replace them if necessary.
The left side hole runs into a black plastic box that can only be seen from the bottom of the car and is not mentioned in any other threads. I have no idea what it does and can’t reach the nuts that hold it on. I can’t see how it would be possible to remove it from the car if whatever it does stops working.

I have considered dropping the cats and replacing them with Nameless cats but it is impossible to get any combination of sockets, universals, or extensions on the two forward most nuts on the right side cat upper flange from above. The outer most nut and above it is 1/4” from the heat shield which has what seems to be the starter cable behind it precluding bending the heat shield to get enough clearance. Can’t get at the heat shield retaining screws to be able to move the cable. The inner most nut has the engine in the way and 2 hoses. I can see the flange and nuts from under the car but can’t reach to touch them or figure how to get a wrench on them or get the nuts back on later.

(As an aside:I considered removing the exhaust system to allow better access and looked at many threads involving replacing it with other configurations. I was very impressed with the fact that of the many changes made for acceptable sound not one person accurately measured if there was a difference in actual performance. I know from my racing days that “seat of the pants” is not an accurate performance gauge. Personally, I prefer a stone silent car that will blow the doors off some noisy attention getter. Their surprise is much more gratifying. Back in the 70’s I had a Norton Commando with engine goodies and quiet mufflers that continually blew off raucous Harleys with straight pipes. It was wonderful to see the shocked look on those trounced noise deafened faces. No, I can’t afforda Tesla.)

Air hammer or impact wrench maybe? Has anyone tried it? Sucessfully?

 

I know what you mean about noise not equating FAST. I had a 'bone stock' 1966 'E' Type back in the early 70's that confounded a bunch of people because a 6 cylinder car was not supposed to be competitive with a V8 Mustang/Camaro/Firebird etc.

The way most people use an air hammer to loosen a bolt (or hex sided O2 sensor) is to 'catch-the-edge' of one point of the hex and angle a dull chisel or blunt point of a hammer bit and 'gently' apply the trigger until you can 'walk' the fastener in a loosening direction. If you get a sharp bit and hammer aggressively you will simply cut the metal hex point off the fastener (or O2 sensor).

Another method is to get a 'crow's foot' or flare-nut wrench and drive it with the air hammer.

 

My upper on the drivers side of my 03 xk8 (non R) came out quick. No rust helped.

 

Thanks motorcarman and brgjag. I appreciate the comments. Will try a crows foot and dull hammer bit.

 

Did you have any luck with the R&R of the O2's?

 

Thanks for replying Gus. I have ordered via Amazon a 17" extra long air chisel bit (need it to reach down to the sensor) and a 7/8 flare nut hex crowfoot. Couldn't find those items around here.
Plan to grind an appropriate notch in the side of the crowfoot to seat the air hammer chisel into and see what happens. May grind the cutting edge of the chisel flat so it hammers, doesn't cut.
Will report what happens.

 

I needed to remove the coolant tank to get access.

My lambda sensor socket had a 3/8 square hole in the end and a 25mm bolt head shape.



First I tried fitting a breaker bar, it would not fit in the space available.

Next a 25mm spanner on the end of the lambda socket, but there was no access to turn it.

Then I used a 3/8 socket ratchet but I could not get any purchase on it.

Finally I used the spanner on the end of the ratchet and it easily freed off the sensor.

 

Thank you RaceDiagnostics. I saw your post earlier and will try that when doing the left side. The right side is my problem and when I get that done will try your method on the left side. Onward through the fog!

 

If you do this with Air Hammer go slow and you will see it start to rotate then you can use an open end wrench.

Gus
www.jagrepair.com

 

Many years ago . . . as I have many years in the bank . . . one of my female employees (it could as well been a male) came into my office crying. She had just receive a bill from a local Volvo dealer for about $1000, that would be $4000 now, to replace an O2 sensor.

The sensor broke off and required the removal of the manifold and exhaust system. Removing the exhaust manifold involving breaking a bolt into the head. That required removing the head along with all the other associated gaskets and one time use head bolts.

I intervened and got the bill reduced to book time for the sensor but the point is that these things can be very difficult to replace.

I use copper anti seize grease installing a sensor. If only the factory did the same.

 

Gus and Test Point: I intend to go very slowly and carefully. Have already mentioned the difficulty getting clearance to reach anything. Thank you for your comments.
The Bosch sensors have anti seize already on them. But I will be sure it is spread evenly and add some if neccesary. The lower sensors once cracked free can be turned with my fingers. That seems unusual as most "bolts" when initially cracked loose usually require a wrench to totally unscrew them.

 

PS: the sensor socket I have is 3/8 drive, not chrome (sometimes chrome plating if not done correctly can cause hydrogen embrittlement which explains how a socket can shatter), and has a narrow slot down the side for the wire. It is different than the sockets such as Snapon S6176 which has about 1/3 of the socket cut away. The Snapon is for 1/2" drive.
Also, I just received the Jaguar XK8 factory manual CD which specifically says use the Snapon socket - but it doesn't tell the route or method to get the socket to the sensor. It just says use that socket to remove the sensor.

 

also just had the p1647 code. I found it easier to removethe converter and replace the 02 sensor on the bench. Took about 3 hrs. Thesame code came back after 1 drive. I think i now need a o2 heater relay whichcan be replaced in about 1 min. Don’t know how to check which is at fault, buti know it’s not the 02 sensor. If there is a way to check out which is at faultit could save a lot of time.

 

To Lifts - I don't know the answer. I know I checked the contacts in the new sensor I installed and it read 0 ohms and 8 ohms on the two circuits.

 

Easy to remove, use a torch to heat around the 02 turn off the fire, then spray with penetrating oil,wait 15 seconds,spray again.