VW Touareg Glow Plug Malfunction Causing Long Preheats

Had the same glow plug issue on my 2018 VW Tiguan diesel. The engine light came on and experienced rough idle during cold starts. Initially thought it was minor, but diagnostic tests confirmed multiple glow plug failures affecting engine combustion. The repair required replacing all glow plugs as a set, even though only two were faulty. This prevents uneven wear and future failures. The job also included cleaning the glow plug holes and checking the control module. While not the most serious issue, neglecting it can lead to starting problems, excess fuel consumption, and potential engine misfire. Watch out for mechanics who only want to replace single glow plugs. The full set replacement is the proper fix. Also ensure they check the wiring harness and control module, as these can cause similar symptoms if damaged. The repair takes about 3-4 hours when done properly. Since your Touareg is still fairly new, this could be covered under warranty. Worth checking before paying for repairs. The symptoms you describe match exactly what I experienced before the fix.

Thanks for sharing your experience. After facing similar issues with my Touareg, I finally got it fixed and the cold start problems are completely gone. Just wondering how much you ended up paying for the full glow plug replacement? Also, have you noticed any other issues since the repair? My engine light hasnt come back on and the rough idle is resolved, but always good to know what to watch out for in the long run with these diesel car repairs.

Got the full glow plug replacement done last week, paid 440€ total including labor and parts. The repair shop did a thorough job checking the entire system. Since the fix, my fuel efficiency has actually improved and the cold start issues are completely resolved. No issues have popped up since the repair. The check engine light has stayed off and the rough idle that was giving me headaches is gone. The engine starts smoothly now, even on cold mornings, and the preheat time is much shorter than before. Make sure you stick to regular maintenance schedules though. While glow plug issues are fairly common in diesel cars, keeping up with service intervals helps catch potential problems early. The key is getting all plugs replaced as a set, this prevents performance variations that can stress the engine. Your Touareg should run perfectly fine now. Just keep an eye on starting performance during the colder months, as thats usually when glow plug problems first show up if theres going to be any issue.

Thanks for the input. Finally got my Touareg sorted out last week. Took it to a different mechanic who actually specializes in diesel engines. The full diagnosis showed exactly what was suspected, faulty glow plugs. Ended up costing 520€ for the complete set replacement plus labor. The repair process was smooth and took about 4 hours. The mechanic showed me the old glow plugs, two were completely shot and the others were starting to fail. Really glad I got them all replaced at once. The cold start is now perfect, no more endless preheating cycles or engine light warnings. The rough idle is completely gone and the engine feels much more responsive, especially during those first morning starts. Fuel consumption has also improved slightly. The mechanic recommended keeping an eye on cold start performance as winter approaches, but so far everything is running great. Definitely worth getting it fixed at a shop that knows what theyre doing with diesel engines.