Why does it sound like a bird chirping - squealing under the hood on a Ford Taurus - Mercury Sable?

Answer 1

Found IT! I just had this problem with my 2002 Taurus. It was a constant chirping that was fairly loud, and would speed up with engine speed, and never go away.

It turns out that the engine in my car has a (I believe I have the name correct) camshaft sensing device. When it goes bad, it's because the shaft sits in a bushing, and the bushing has worn out. The mechanic told me Ford used these only on this car, and a truck. Why they used a bushing instead of a bearing makes no sense to me.

If you get a cam sensor code, consider if you've been hearing a squeak noise like a belt chirp that doesn't go away when you replace the belt. If so, use a prybar or similar tool to press down on the synchro. If the noise goes away replace both the sensor and the synchro.

Depending on the mileage, it's fairly certain you need to replace the belt. If the mileage is fairly high, it would be a good idea to replace the belt tensioner at the same time.

The tensioner is a spring-loaded pulley that keeps tension on the belt and it, too, wears down in time.

That would be the Synchronizer Assembly. Its actually a "dummy distributor" that's located under the throttle body, under the black, wide flat wiring harness cover.

The cam position sensor is mounted on top of the assembly. Its a major chore to change out and really needs to be fixed before it seizes up and does more damage.