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Serp belt noise

more of a rattle from serp belt area vs a squeak. turning a/c on/off made no difference. I could hear the rattle from the driver seat. it seemed to vary based on engine temp. loosened tensioner and took belt off 1 of the accessories but I did not completely remove belt. spun all components. water pump, power steering, idler pulley, tensioner pulley. all seemed tight. I put belt back on #1 accessory and belt is quiet. noise/rattle/squeak is gone. whats up?

My wild guess, and it’s only that, is that when you removed and reinstalled the belt you affected the tensioner in a way that made the noise disappear. Your tensioner includes in it a spring -loaded part that keeps the belt taught. Perhaps it just needed to “stretch its legs”. My guess is that you’ll eventually need to replace the tensioner due to wear.


tensioner? belt makes noise. chirp could certainly come from poor/erratic tension. I know it would be pretty quiet with no tension.

My 2003 Taurus had a chirping noise that came from the cam synchronizer bearing. If your Taurus starts chirping again you might want to check it. The cam synchronizer replaces the distributor on the Vulcan V6 (OHC). It’s a common problem on this vintage Taurus. An engine stethoscope will confirm it.



Did change idler and tensioner pulleys in last yr. newer WP. Alt is 3-4 yrs old. Napa? They never fail. Did read about synchronizer issue awhile back. I do like the tensioner comment though. Belt made noise. Loosened belt, tightened belt. No noise. Hmm.

We had the same symptoms recently in my '96 Explorer and the tensioner failed requiring the car’s first-ever tow. You could be looking at waiting around for a tow truck in an undesirable location, an overheated engine, and failure to show up for work on time. When the tensioner failed I pulled off immediately and am glad I did.

So … I’d inspect and probably replace the tensioner.

In the meantime, keep an eye on the gauges and if the tensioner fails, pull off immediately before the water stops circulating in the engine. You may also want to keep a container of anti-freeze and some radiator stop-leak (if you use that stuff, though, it will likely clog your thermostat and possibly your water pump so plan on some expense. Oh, and perhaps check to see you have tow service included in your insurance (although even here, there are some limits to the policy, how far they will tow you, and which shops you can use).

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Perhaps the best suggestion of all.
If the tensioner fails, the OP will probably only be good for about 10 or 15 miles max before the battery is drained anyway, depending on the engine, battery, and a few other variables. That is, however, enough to allow the engine to overheat (if the pump is belt driven) and begin destroying itself. Better to be prepared to get towed.

Understand, of course, that a bad tensioner is only an educated (?) guess by me. I hope cavell posts back when the actual source of the sound is isolated.