Tip: Revised Spark Plug by Volkswagen

  At the end of September 2011, Volkswagen launched a revised spark plug for the 1.4 TSI Twin-charged engine (CAV-) with the part number 03C 905 601 A, in order to replace the older units (part number: 101905626). 

  The actual change is the gap setting. The revised spark plug is preset to 0.80mm instead of 0.92mm (older unit). Apart from that, they appear to be identical, as they both have the same heat setting, they both feature a platinum needle tip and all dimensions are the same as well.
  According to customer statements, the engine now runs smoother, eliminating specific misfiring issues. 
  As far as we know the revised spark plugs is not part of a recall campaign or technical bulletin but the owners are advised to have the revised units fitted. We should note that it is not suggested to re-gap the original spark plugs as they have a very thin platinum needle tip which is prone to get damaged or even break in case of re-adjustment.