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Hello everyone. I feel really stupid. I have a X100, 2001 Jaguar XKR with a P1646 code. It means the upper heated oxygen sensor bank A has failed. I have the replacement part in hand. After removing the air plenum from the throttle body and MAF sensor, I can't see the O2 sensor. I tried the forums, but only got help for a S-model. I have the special socket with the slit opening, but cannot see where the sensor is located.Can anyone help with a photo or some dialogue to guide me please?
I don’t recall whether that is drivers side or passenger side...
Drivers side: directly below the coolant expansion tank. You will have to move it out of the way.
Passengers side: once you have rmoved the air intake duct, it should benear the back end of the engine. In both cases the sensor is on the exhaust manifold. They will have a wire that runs and connects behind the throttle body. You are going to see 4 of them connected, you will have to figure out which is the one you want.
Apart from not being able to get my large hands on the upper sensor, they are often so tight that the only way to get sufficient leverage is off the vehicle. For this reason I drop the Cats and do the change on the bench.
If you do it this way, ALWAYS replace manifold to Cat studs and nuts. It ensures a gas tight joint on reassembly and saves a lot of grief if it ever has to come apart again.
Hello Michael. Merry Christmas and a most happy new year to you. Thank you for the picture. It helps a lot. I just woke up (It is 9 am here). I plan to read the thread you provided right after morning coffee. My best regards, Bob G in Florida
I decided to read through the thread you suggested while drinking morning coffee. Great experience. Confusion abounds. Took me almost an hour to read all the posts and replies. Conclusion. There might be an error in the documentation (secondary fuel pump vs O2 sensor), but it might depend on your year and model. In all cases, my issue is the heated portion of the oxygen sensor. Today's plan is to find the grey connector, measure resistance for the heating element. Thank you again my Jersey, Channel Islands friend. You are always the best source of great information for me. Best regards, Bob G in Florida
A belated Merry Christmas and Happy New Year to you too, Bob.
Looking at Graham's picture, you should be able to get a multimeter on the connectors to do the checks. I hope the link didn't prove to be too much of a diversion - this code has been discussed a few times here & there's still no definitive answer
Late yesterday I received the 2 Ohm, 100 Watt Resistor, from China, US $0.99 including shipping. Photo attached.
Weather permitting, this weekend I will attempt to cut HEATER only wires from existing (installed) H2O Sensor at connector, and reroute to this device. I hope that the computer recognizes the 2 ohms during startup until engine reaches temperature (about 1-2 minutes). If successful, I will post for others to consider.
Cheers (wish me luck)
Bob Grisar (your friend in Florida)[img]c:\Users\rgris\Desktop\2 Ohm, 100 Watt Resistor, IMG_6838.JPG[/img][img]c:/Users/rgris/Desktop/2 Ohm, 100 Watt Resistor, IMG_6838.JPG[/img]
^^ 99 cents including shipping? I know China is haphazardly attempting to capture the bulk of the world electronic components market but that has to be the best example of a money-losing proposition that I have heard about in a long, long time....
If you do end up doing one, I recommend doing all 4. I am so glad I did. Tried to onesy twosy my XJR and ended up doing 3 within 2 years. I did all 4 at once on my car; it's like 200-250 for decent sensors.
Hello Mike. How's the weather in Jersey Islands, now that spring has finally arrived?
After a three-month absence (long story), I today finally located the connector for my 2001 Jaguar XKR passenger side HO2S. What a PITA. With help from a slip joint pliers, I was able to get the connector off the mount, and separate.
My ohmmeter confirmed the heater wiring is an open circuit, which is different from the other side that measured 2 ohms. So using some string, I looped each end of the gray connector pair, and tied them up so I don't have to squeeze in there again trying to find them. Now I want to gain access to either end of the wiring (sensor pigtail or hardness) to snap in a pair of wire crimps. I can't get enough slack in either end to continue with my plan. I am wide-open to all suggestions short of lifting the engine out of the car.
Welcome back Bob and I hope you're well. Spring came and wented over the Easter weekend so we're trailing Florida by a good margin at the moment
If you're trying the resistor method find somewhere clear of any plastic to mount it. It will dissipate at least 72 watts so it's going to get HOT. I suspect you'll have to bite the bullet at some point and replace the sensor - and likely the others too if they are original.
I hope that your month of May starts off on the right foot.
In my last post, I was lamenting that there was very little room to get my hand into the O2 connector area to attempt a splice. Well, I have great news. For US$7, I found an O2 connector extension. Picture follows. Since I was able to successfully separate the halves of the connector, all I need to do is insert my China 100W 2 Ohm resistor across the proper pair of wires, and mount the resistor on the firewall where there is plenty of room. Delivery date for the extension is 23 May, so perhaps by the end of the month I will have defeated the failure prone heater in the HO2S, by bypassing it with an US$1.50 external 100W 2 Ohm resistor and a US$7.00 cable extension. If it works, it save me US$250 for the part, and another US$300 for the labor. I'll keep you posted. Universal Oxygen Sensor Extension Cable from eBay.
12-27-2018, 01:31 PM
Help - Need to replace the upper HO2S Bank A
