Hello!, My engine has a knock or tick at certain RPMS. I dont know the RPMs as i do not have a RPM gauge, but i would guess around 2500rpms? It does not affect the driveability of the car, but this sound is a little annoying. The car has 101K miles on it, I'm using Pennzoil Plat 5W30 and a Fl-400s Motorcraft filter. Oil was just changed 100 miles ago. Have been using syn from 96K miles. This problem has always been here from day 1 @ 96K miles. I dont think it is getting worse. The car could be a city car... :o I'm not too worried about this problem, because the 89 Cougar LS we had also had this problem and also a idle tick/knock, and at 196K miles, was still running, but i would like to know just what the problem is. Thanks! Just the normal idle.