BRITISHPARTS.CO.UK TERRIBLE COMPANY TO DEAL WITH. Ordered lambda sensors. Sales department were so confident the parts were correct but had same issues immediately after fitting them.  If you have ordered from British Parts and they are not working have the resistance checked. Totally wrong!  Supplied sensors reading 3oms proper ones ordered from elsewhere reading 15. Tolerence is 12-18. Refused to return unopened box as it's just over 14 days. I accept the first two were just out of time limit - only because we thought the parts supllied were properly manufactured which wasn't the case in my opinion and that of an expert with excellent diagnostic equipment. Please don't assume as I did that they know what they are talking about because they sound confident on the phone. If the new parts fitted are causing issues, check the parts have been manufactured to a standard. I'm told they have never had anyone claim the resistance is incorrect. Had I not met an industry specialist, I too would have blamed everything but the oxygen sensors. No longer will I recommend British Parts. All the garages I worked with have agreed to remove them from their preferred suppliers list. We are lucky in the north east England we have a specialist who is used by major vehicle suppliers for indepth diagnostics. It is my understanding the normal tolerance for oxygen sensors is between 12-18 oms for them to read correctly. The ones supplied are 3. This is a huge difference! This is a true statement to help others facing the same issue for parts purchased from British Parts and facing dilemmas. This is not your typical handheld or laptop diagnostics. This is next level diagnostics with a clear solution.  Have you had similar issue but did not report it to British Parts and assumed the problem is elsewhere. Please recheck the issue, I will point you in the right direction. I am not involved with the diagnostics company but feel let down with over confident sales staff at British Parts and will air my views on each and every platform available to me. This is an honest review after months of distress and being let down by British Parts.  Please don't assume the parts can't be faulty or poorly manufactured. I assumed they were genuine parts. Landrover were more expensive, but I have paid several times more in the end after paying for diagnostics and new sensors and unable to return the faulty ones. British Parts have lost a customer and trade business through their unfair policy.  This is based on my opinion and the opinion of experts in the field with state of the art diagnostics equipment. BUYER BE AWARE!!!! ___________________ Update after response  You were clearly informed the one recently ordered has not been opened. But you refuse to return it as it's a few days over your 14 day policy. We ordered new ones from Land Rover which worked straight away. We assumed your parts were tested and guaranteed as you keep claiming. Do you want to test the resistance on your lambda sensors? I am offering you a live challenge. There is no fault in the vehicle other than your sensors. I am willing to order a new pair for the purpose of test only. They can be delivered straight to the diagnostics centre. An independent impartial professional tester will test them. ARE YOU WILLING TO PARTICIPATE LIVE ON FACEBOOK, YOUTUBE, INSTAGRAM? Please let me know and I'll arrange an honest test. Please speak to the tester or the owner of the testing facility.  The point of these review sites is to make others aware. You are a professional company, however, these are not manufactured to a suitable standard. They did not pass the test. I personally do not possess the knowledge but these experts do. The staff at British Parts said on two occasions they are not mechanics which is fair enough.  No one is claiming the parts are incorrect for the vehicle yes they do fit the description and match chassis number they are not correct polarity they are well below the tolerance levels. Please understand the complaint!