What are the symptoms of a faulty alternator tensioner pulley?
2 Answers
Generator tensioner pulley failure manifests as sudden increase in engine noise during rapid acceleration (especially around 1500 RPM), engine timing chain skipping teeth, ignition and valve timing disorders, engine vibration, and difficulty starting (severe cases may prevent starting altogether). When these symptoms occur, the tensioner pulley should be inspected for damage. The tensioner pulley is a wearable automotive component - prolonged belt usage can cause stretching, though some tensioners automatically adjust belt tension. Additionally, proper tensioner pulley function ensures smoother vehicle operation, reduced noise, and effective prevention of belt slippage.
A faulty alternator tensioner will exhibit some obvious signs. My old car had this issue before - as soon as I started driving, there would be squeaking sounds from the engine compartment like a mouse chirping, especially noticeable when accelerating. If driven longer, the noise would turn into roaring or grinding sounds, making the whole car feel like it was vibrating. After parking, I checked and found the belt was loosely jumping around, which usually indicates the tensioner bearing is worn out and can't properly secure the belt. More troublesome was that the alternator charging performance also deteriorated, with the battery light occasionally flickering. If not repaired promptly, the belt could even come off completely, leaving the AC inoperable. I've always remembered this lesson - during every maintenance session I remind the mechanic to thoroughly inspect the tensioner to avoid roadside breakdowns that waste both time and money.
