VW Bora Glow Plug Issues Impact Fuel Economy

I had a very similar issue with my 2004 VW Golf TDI. Having some experience with diesel engines, I recognized those classic glow plug symptoms right away. The check engine light came on and cold starts became really rough. The engine misfire was quite noticeable, especially on cold mornings. After scanning the error codes, it pointed to a faulty glow plug in cylinder 2. Took it to my regular workshop where they diagnosed and confirmed a defective glow plug. They replaced the faulty unit and checked the others as preventive maintenance. The total cost came to 440€ including parts and labor. Since the repair, cold starts are smooth again and fuel consumption is back to normal. What specific error code is your system showing? Have you noticed if the cold start issues are worse in certain weather conditions? This information would help determine if your symptoms match what I experienced. Also, could you share your mileage? At higher mileages, it might be worth checking all glow plugs since they tend to wear at similar rates.

Last service was done 2500km ago, but with 124548km total on the clock, I think its time to address this properly. Thanks for the detailed info about your repair experience. The error code Im getting is P0671. Cold starts have definitely become worse lately with a rough idle until the engine warms up. The poor fuel economy is really noticeable too, burning through a tank much faster than usual. The service history shows the glow plugs were never changed. Based on your experience, sounds like I should have them all checked and probably replaced as a set. Good to know a ballpark cost figure, helps with planning the repair budget. Did they recommend any specific brand of glow plugs for your diesel car repair? Just want to make sure I get quality parts installed.

Thanks for following up with those details. Yes, that P0671 code is exactly what I had, it indicates cylinder 1 glow plug circuit malfunction. With your mileage being similar to what mine was, replacing the full set of glow plugs makes a lot of sense. For my diesel engine repair, the workshop used Bosch glow plugs, which have been running perfectly for the past 2 years. They explained that using OEM or premium quality parts is crucial for reliable cold start performance and proper engine combustion. The complete set replacement actually worked out more cost-effective than just doing one, since most of the labor cost is in accessing the plugs. The slightly higher parts cost was worth avoiding potential future issues with the other aging plugs. A tip from my experience: have them check the glow plug wiring harness during the repair. Sometimes the connections can deteriorate and cause similar symptoms. In my case, they found some minor corrosion and cleaned the contacts while they were in there. The improvement in cold start performance and fuel economy after the repair was significant. The engine went from a rough, smoky start to smooth operation within seconds of turning the key.

With my mileage milestone and the P0671 code showing glow plug issues in cylinder 1, I think moving forward with a complete set replacement is the sensible choice. Its reassuring to hear Bosch parts worked well in your diesel car, will definitely request those when booking the repair. Good point about the wiring harness check. Given the rough idle and fuel efficiency problems Im experiencing, having them inspect the connections makes complete sense. Rather find and fix any corrosion issues while theyre doing the glow plug replacement. Looking at around 440€ for the full job seems reasonable, especially if it solves both the cold start problems and gets my fuel consumption back to normal. Will book it in next week and get this sorted before the engine misfire gets any worse. Thanks for sharing your repair experience. Really helped confirm my suspicions about the glow plugs and gave me a clear picture of what needs doing. Will update once its fixed to let others know how it went.