I'm really sorry for picking this problem up again, but I'm really totally lost and don't know what to do. That's why I'm calling for your help guys.

After I have rebuild my 4G H22 (new rings+bearings) and changed my timing belt, the engine makes this sound at 1000 RPM: http://www.volny.cz/veitel/prelude/vtec.mp3.

1) The sound comes only at approx. 1000RPM, nowhere else. Dosn't matter if the engine is cold or warm, doen't matter if I go or stop. It seems that the sound comes from the inside of the engine itself (head or block, form the side of the timing belt).

2) I tried to remove the PS pump, alternator and A/C. No change. I also removed both the crankshaft pulleys, no change.

3) I removed the timing belt gear on the crankshaft, cleaned it, greased the hole in it (no the belt itself) and returned back. I thought there could be some clearence. No change.

4) The autotensioner and adjusting pulley were replaced for the manual H23 one. No change.

5) I removed the balancer belt, no change.

6) I changed the water pump, no change.

The sound disapperas at some conditions: When I set the timing belt tension according to the Helm's, the belt is pretty tight (same as with the autotensioner) and the sound is there (again same as with the autotensioner). When I make it little loose, the sound dissapears, but the belt itself vibrates a bit (about +-0.5cm on its way between the exhaust camshaft and crankshaft). With the autotensioner (when the tension is set right), the sound is still there.

WTF can this be? Why the sound stops squeaking when I loose the timing belt? The timing belt and all around there is brand new and correctly instaled, valves are set to spec. What else is directly connected to the timing belt?

The engine has 50000 miles and runs strong. I don't want to destroy it :-(.