Audi A1 Diesel Glow Plug Control Unit Failure Alert

Had the same issue with a 2015 Audi A3 diesel engine. The constant preheating light combined with dark smoke typically points to glow plug system problems. During acceleration, the engine misfire was quite noticeable in my case. The diagnostic showed two main problems: faulty wiring connections to the glow plugs and a failing glow plug control module. The heating element in one plug was completely dead, causing incomplete fuel combustion. This turned out to be a serious issue requiring immediate attention, as continuing to drive risks damaging the engine further. Poor cold starts and excessive smoke can lead to carbon buildup and reduced engine performance. The car maintenance involved replacing the control module, rewiring the connections, and changing all glow plugs as a preventive measure. The engine light cleared after repairs and cold starts improved significantly. For accurate diagnosis, suggest getting the glow plug resistance tested individually and having the wiring connections checked before replacing parts. The symptoms match classic glow plug system failure patterns in these models.

Thanks for sharing your A3 experience. I had very similar problems with my A1 last winter, black smoke and those annoying warning lights. The mechanic found issues with the glow plug control unit and had to replace it along with two faulty glow plugs. The diagnostic test was spot on in my case, and the cold start problems disappeared completely after the repair. Been about 8 months now with no issues. Would you mind sharing how much the full repair cost you? And has everything stayed fixed since the work was done?

Glad to hear you got similar issues resolved on your A1. For my A3, I actually just had it fixed last week after the vehicle stalling became more frequent. The diagnostic test confirmed it was indeed the glow control unit causing problems. Unlike your case where glow plugs needed replacement, my issue was simpler, just a faulty connection to the control unit that needed repair. Total cost came to 95 Euro for fixing the wiring. Much cheaper than initially expected, especially compared to a full glow plug replacement. Since the repair, the heating element system works perfectly. No more dark smoke during acceleration, engine misfire issues cleared up, and cold starts are smooth again. The warning lights haven't returned, which confirms the mechanic correctly identified the root cause. The quick fix saved money compared to replacing the entire unit. Would suggest others with similar symptoms get a thorough diagnostic before assuming worst-case repairs are needed.

Thanks for the details about your repair costs. Finally went to get my A1 checked after putting it off for too long. The diagnostic test revealed exactly what you mentioned, faulty control unit and bad wiring connections. Total repair came to 380 Euro including new glow plugs and labor. The engine light issues and smoke problems cleared up right away. Cold starts are working perfectly now and no more diesel engine problems during acceleration. Really glad I got it fixed before winter. Definitely learned my lesson about not waiting too long when these symptoms show up. The mechanic was thorough and showed me the worn heating elements in the old glow plugs. Having driven it for 3 weeks now, everything seems fixed and running smoothly.