{"product_id":"post-cat-lambda-oxygen-sensor-fits-jaguar-xf-i-x250-3050-2008-15-dx239g444fa","title":"Oxygen Sensor – After Catalyst – Jaguar XF X250 – 2008-2015 – DX239G444FA","description":"\u003cp\u003eThis direct-fit oxygen sensor (exhaust gas sensor \/ pre-cat sensor) restores correct air-fuel mixture, fuel economy and emissions performance on the Jaguar XF I X250 (2008–2015). Built to OEM specification and matching part numbers C2D23703, C2D54167, T2R54607, 02T2R54607 and DX23-9G444-FC.\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. Position: Rear, Post Cat.\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":57283732930904,"sku":"180","price":62.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0947\/3373\/0136\/files\/SKU180_C2D23703-6_updated_2823d744-dbc9-4fbc-b84c-2383aa3b4238.jpg?v=1780996079","url":"https:\/\/carpartclubs.com\/products\/post-cat-lambda-oxygen-sensor-fits-jaguar-xf-i-x250-3050-2008-15-dx239g444fa","provider":"CarPartClubs","version":"1.0","type":"link"}