Serpentine belt is on OK
I see no broken belts -- any more belts other than serpentine?
Any idea where to look, or should I just tow to the shop
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2000 Mercedes-Benz S500 Question: "Check engine" on - engine sluggish Thumping sounds - like a belt hitting side
Answer #1M & R Car Import Services II, Inc (65 Answers) , Chicago, IL - (773) 840-8204M and R Car Import November 12, 2013, 23:47Technician
Your vehicle is equipped only with one engine serpentine belt. NOT to be confuse with internal metal timing chain. I personally think an ounce of prevention is worth a pound of cure. Towing the vehicle ta a nearby qualified independent service center wound minimize any additional stress on vehicle. Make sure you either show or point out when, and how to duplicate said "Thump" noise so it can be addressed. Best of Wishes.