The 'emissions service workshop' light came on yesterday morning. Scanned it last night and VCDS reported and 'open in glow plug #4 circuit'. I reset the fault, cycled it a few times, no more problem. This morning, still no problem. So the question, do I remove the glow plug and 'look' at it? What to look for? Is this a sign of future trouble for the GP and I should just replace it now? I will start with the electrical connection first. Advise would be appreciated.