{"product_id":"post-cat-lambda-oxygen-sensor-fits-jaguar-xj-x350-303642-2003-09-c2c22679","title":"Oxygen Sensor – After Catalyst – Jaguar XJ X350 – 2003-2009 – C2C22679","description":"\u003cp\u003eReplace your failing oxygen sensor — also called a pre-cat sensor or post-cat sensor — on the Jaguar XJ X350 (2003–2009) with this OEM-spec direct fit. Matching part numbers 6R83-9G444-AB, C2C22679, C2C8442, 149100-8100 and 234-4951.\u003c\/p\u003e\n\u003ch3\u003eCommon signs of failure\u003c\/h3\u003e\n\u003cp\u003eA failing lambda or oxygen sensor will turn on the check engine light and commonly log fault codes in the P0130–P0167 range (sensor circuit and heater faults). Drivers typically notice a sudden drop in fuel economy, rough or fluctuating idle, hesitation under load, a sulphur or rotten-egg smell from the exhaust, and in many cases an MOT emissions failure. On modern diesels and direct-injection petrols, a stuck or slow-responding sensor can also push the engine into limp mode.\u003c\/p\u003e\n\u003ch3\u003eFitment notes\u003c\/h3\u003e\n\u003cp\u003ePlug-and-play installation with the correct factory connector — no diagnostic coding required. Most engines run a pre-cat (upstream) and a post-cat (downstream) sensor; cross-check your existing part number and the position on the exhaust to make sure you're ordering the right one. Apply a smear of anti-seize compound on the threads before fitting and torque to manufacturer spec.\u003c\/p\u003e\n\u003ch3\u003eFrequently asked questions\u003c\/h3\u003e\n\u003ch4\u003eHow do I know if my lambda sensor is faulty?\u003c\/h4\u003e\n\u003cp\u003eAn OBD2 scan showing P0130-series codes plus poor fuel economy is the clearest sign. Live data showing the sensor stuck at a flat voltage (instead of oscillating between roughly 0.1V and 0.9V) confirms a faulty sensor.\u003c\/p\u003e\n\u003ch4\u003ePre-cat or post-cat — which one do I need?\u003c\/h4\u003e\n\u003cp\u003ePre-cat sensors (upstream of the catalytic converter) control the fuel mixture. Post-cat sensors (downstream) monitor catalyst efficiency. Match the OEM number on your old sensor to the numbers listed above to be sure.\u003c\/p\u003e\n\u003ch4\u003eWill a new sensor fix my fuel economy?\u003c\/h4\u003e\n\u003cp\u003eIf the original sensor is biased lean or rich, a correct replacement typically restores MPG within a tank or two of fuel. Drive at least 20-30 miles after fitting to allow the ECU to re-learn.\u003c\/p\u003e","brand":"PitShopUK","offers":[{"title":"Default Title","offer_id":57283739255128,"sku":"213","price":54.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0947\/3373\/0136\/files\/SKU213_2_updated_3470f029-6cec-461f-a41f-0d707255d78f.jpg?v=1781190271","url":"https:\/\/carpartclubs.com\/products\/post-cat-lambda-oxygen-sensor-fits-jaguar-xj-x350-303642-2003-09-c2c22679","provider":"CarPartClubs","version":"1.0","type":"link"}