Q: Serpentine belt keeps coming off

asked by on November 28, 2016

Never had this problem before I'm thinking it's one of the Pulleys . And do they just go out of line ? I don't know

My car has 15000 miles.
My car has an automatic transmission.

The pulleys will not just lose their alignment. For this to happen, there has been a failure somewhere. One of the most common causes I have found for this problem, on a serpentine belt system, is that the belt tensioner has failed and the pulley allows the belt to move around. However, the best way to troubleshoot the situation would be to remove the serpentine belt and check each individual component. Check the pulleys on each component to see if a bearing has too much play in it, or if something has loosened up and allowed the component to move around. If this is something you feel you could use a hand identifying and/or fixing, contact a certified mechanic, like those available at YourMechanic.com.

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