car did not pass smog , HC too high . at 25 mph HC is 61, 45 allowed. The rest is good. Just recently changes spark plugs wires and rotor, but O2 sensor is from 2010.
trying to locate O2 sensor and do I need a special tool to change it / without dropping exhaust ? gina
Does your car have one O2 sensor or two?
as far as I know one O2 sensor (down exhaust down pipe).As it turns out my dash temp indicator is on 0. Have to trouble shoot the wire ing and temp sensor I guess. Could that be the reason for high HC and not passing smog ? with warm regards Gina
Hi Gina, the dash gauge has no effect on the running of the engine, the sender for this is the singe pin sensor on the thermostat housing, the one with 2 pins next to it is the one that talks to the ECU and has an impact on the engine running.
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No special tool, just a spanner. I can’t remember the size though, it’s a bit tight to get to, the O2 sensors are just before the Cats; where the two exhaust manifolds dump into one pipe - the wide bit.
Hi Gina,
I had this problem back in 2004 in CT. We kept most of our cars in SC but they were all registered in CT and my 95 would not pass so I did what most people do, start replacing parts in hopes that by process of elimination I will finally solve the problem. Three dealers could not figure it out as the car was also running rich and you could smell fuel from the exhaust. I did everything you could think of to avoid spending too much guessing money. CT sent a letter stating that if I did not pass I would loose the registration but after trying 4 times at $20 each the head of that dept told me I would not and I did not. Just a money making scheme. Here was the problem after burning out both catalytic converters over time; a tech at the dealer in Charleston, SC found that my air pump was bad. I replaced it as I had a spare being in the XJS parts business. Problem solved. The air pump should come on periodically just after cold start is best for checking. It is located on your car just under the air cleaner housing on the left side where the black plastic hose connects to the air cleaner housing. If this is the problem or not I urge you not to listen to people suggesting you throw out the pump. For one if missing your check engine light will come on and stay on and you will never pass inspection. Secondly I saw a Hagerty seminar with some of the top appraisers and collectors on the panel including Wayne Carini and they all agreed that many of the cars that had the air pumps thrown out are now worth a lot of money and collectors want the car completely original and now that these pumps can not be found will dramatically devalue the car and in some cases a deal breaker. And yes in two of the videos they mentioned the XJS becoming a serous collectible very soon. Look at the prices lately.
LeRoy
Does this air pump run when the car is warmed up? Because it does not on the V12; a running air pump would confuse the O2 sensors.
Correct. The well-known to all 6.0L V12 owners FF66.
The air-injection is energized by the 36CU periodically after the engine reaches operating temperature and, as explained to me by R. Bywater, this was built in so that the fucntionallity of the system can be tested.
The problem is, again, as many of us know, the holes for the air-injection get almost completely blocked by heavy carbon deposits, and as a result, the ECU doesn’t see the needed change in the O2-sensor output, thereby flagging the FF66 code.
The good news, at least for me, was that it is a line of code – Roger took it out from my ECU.
I assume the 6-bangers (prior to the AJ16, which is OBD-II) are functioning the same way.
Steve
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Hi Leroy, just reread your airpump comments. great suggestion !!
well ,still hunting for rich fuel reason . My air pump hoses and stuff leading up to airpump has 'fallen" out and sitting in engine bay loose. So i shall order rubber grommets to put it back together and I am working / posted this : , trying to follow the wire harness in between fuelrails towards middle of firewall , (esp. babyblue wire with sm. orange markers) starting point (temp .coolant sensor)air coolant sensor. Harness then goes towards passenger side along firewall and goes down into firewall. Also 2 black rubber hoses ( vaccum ?) and a reddish clear tiny plastic hose.bundled with harness in thick rubber boot. Where does the harness continues and leads to fuel Ecu passenger side in trunk. I am supposed to have Continuity on ECU pin 5 per diagram. Mice have been in car !
. Car runs very rich , failed smog and think I have temp coolant sensor issues, I already replaced the sensor and have continuity from (sensor) wire to firewall. please help
The correct tool can be obtained from the better tool suppliers.
Very expensive, so what we do is take a spark plug socket and cut a slot to clear the O2 sensor wire(s).
I have some new O2 sensors and no longer have a Jaguar.
I just realized my O2 sensors are from the 6.0 V12.
Please contact me offline 650.455.1110