VW Golf Belt Tensioner Squeal Points to Failed Parts

I dealt with a very similar issue on my VW Jetta from around the same period. Having some experience with basic car maintenance, I recognized those belt squeal symptoms right away. The serpentine belt system started making those exact noises, particularly during cold starts. At first I tried checking the belt tension manually, but quickly realized the tensioner pulley was the real culprit. The belt tensioner had lost its proper spring tension, causing inconsistent pressure on the serpentine belt. Took it to my regular workshop where they confirmed the diagnosis. They replaced both the tensioner and the serpentine belt as a preventive measure, which cost 455€ total. The repair took about 2 hours since they had to remove several components to access the belt system properly. The timing belt was also inspected while they were in there, which I recommend having checked since they are working in that area anyway. After the repair, all belt squeal noises completely disappeared and engine performance returned to normal. To better assist with your situation, could you share: Which Golf model year you have, Current mileage, Whether the noise changes with engine RPM, If you notice any visible wear on the serpentine belt This information would help determine if your symptoms match what I experienced.

Last service was done at 75000km and the issue started shortly after. My serpentine belt does show some visible wear marks on the edges and the noise definitely varies with engine RPM, getting louder at higher revs. When checking under the hood, there is a clear fluttering movement of the belt drive system. The belt tensioner seems to have more play than normal when checked manually. Based on responses here, it seems replacing both the tensioner and belt would be the safest approach for proper automobile maintenance. Will update the thread after getting it checked professionally.

Thanks for the follow-up details. Those symptoms perfectly match what I experienced with my Jetta, the RPM-dependent noise and visible belt wear are classic signs of a failing tensioner pulley. The fluttering you mentioned is particularly concerning, as it matches exactly what I saw before my repair. The timing between your last service and the issue arising is interesting. On my car, the tensioner started failing around 80000km, very close to your mileage. The idler pulley was also showing wear when they did the repair. Since you mentioned visible belt wear and flutter, I strongly suggest not waiting too long. When my tensioner fully failed, it caused the belt to slip badly, leading to engine noise and reduced engine performance. The repair shop ended up replacing: Belt tensioner assembly, Serpentine belt, Idler pulley (as it had worn unevenly) Total repair time was around 2 hours and cost 455€, but preventing potential damage to other components made it worthwhile. The engine performance improvement after the fix was noticeable. Keep monitoring the noise level, but based on the symptoms you described, your diagnosis seems spot-on. Planning for a tensioner replacement soon would be a smart preventive measure.

Thanks for everyone's detailed responses. After monitoring the symptoms more closely over the past few days, I'm now certain about moving forward with the repair. The automobile maintenance diagnosis pointing to the belt tensioner system makes complete sense given what I'm experiencing. The serpentine belt definitely shows concerning wear patterns, and the tensioner pulley movement seems even more erratic than before. The flutter in the belt drive gets particularly bad at higher RPMs, which matches what others described. I've scheduled an appointment with a local shop for next week. Based on the feedback here, I'll have them check both the idler pulley and belt tensioner assembly while they're working on it. The 455€ cost estimate seems reasonable considering the components and labor involved. One thing I noticed today, the belt squeal during cold starts is getting more frequent, so this repair timing feels right. Will make sure they do a full inspection of the entire belt drive system while they're in there. Thanks again for helping confirm my initial diagnosis. The detailed repair experiences shared here gave me a much clearer picture of what to expect.