I had the belt replace in a garage about a month ago because it was slipping off and it fell off again about a week ago. I found out that the belt tensioner was busted. I replaced the tensioner now it is not lining up. it keeps slipping off the crank shaft and sliding off the idler pulley but not completely off.
The pulleys may not be lined up in the same plane. Look at the harmonic balancer and crank pulley in particular. The rubber bond in the balancer may have failed thus causing misalignment of the pulleys relative to the other pulleys. The other issue is be sure you have the correct replacement belt and the correct tensioner.
If you request serpentine belt inspection/replacement a certified Mechanic, dispatched by YourMechanic right to your location, will get the belt issue resolved for you promptly and the mechanic will of course let you know if you need a new harmonic balancer/crank pulley. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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