Ford Repair: Ford Taurus 1999 - high-pitched sound + check engine soon, ford taurus, 1999 ford taurus

Question
1999 Ford Taurus mileage: 140,000. This last time it had an intermittent very high-pitched sound when driving anywhere from 10 to 50 miles per hour.  It seems during acceleration.  It occurs 50% of the time. Also the check engine soon sign went on. What could it be and what does a repair usually cost? Thx for help, Thorsten

Answer
is it a squeak-chirping type noise if it is it's probable a cam synchronizer have it scanned and see if you get a cam position sensor code if so thats going to be it-off the top of my head i think it would be around 225-300 dollars for a ford part-i think there are some aftermarket now i  haven't used any though-good luck