Hi, Put my car on VAG-COM and got the same code! 00542 - Needle lift sensor (G80) 30.10 - Open or short to B+ this is on a 2.5 V6 TDi, 2001. spoke with Audi and a mate at VW. Audi wouldn't give me any information about the part or fault unless i paid them to put my car on their diagnostics system to give them te same error code i did!! Alan (customer services guy, nice chap) told me the name of a company who can refurb the unit and that its not that of a UNcommon fault! However, VW, my mate called an engineer over who told me that the needle lift sensor is (on most diesel engines) inside the INJECTOR PUMP unit..costing £1436.00 + VAT on an exchange basis! /ubbthreads/images/graemlins/frown.gif Good job i was already sat down!!! Could be lucky, the sensor mght not be in the unit (but knowing my luck...it WILL be!) Only way I will defo know is to give car to Audi and let them check it! Details of the company that Audi told me about can be found HERE! I've emailed them and as soon as I get a response I will post back. has anyone ever cleaned/opened and injection pump???