I CONTACTED THE LOCAL DEALER AS WELL AS PORSCHE(ATLANTA OFFICE). ALMOST EVERYONE WITH A 944S OR 1989-91 944S2 HAS REPORTED THIS FAILURE OR DEFECT. THE CAM CHAIN TENSIONER HAS A PLASTIC RAMP WHICH CRACKS AND FAILS CAUSING CATASTROPHIC ENGINE FAILURE. PLEASE LOOK ON WWW.RENNLIST.COM UNDER 944 SITE. DO A SEARCH ON CAM TENSIONER AND YOU WILL SEE HOW MANY PEOPLE ARE HAVING THIS PROBLEM. PORSCHE SAYS THERE IS NO PROBLEM AND WILL NOT ISSUE A SERVICE BULLETIN FOR AN INSPECTION INTERVAL. THE PLASTIC RUNNER BEGINS TO CRACK AND THEN FAILS CAUSING THE CHAIN TO CATCH AND COME APART. VALVES/PISTONS COLLIDE CAUSING CATASTOPHIC FAILURE. PART REPLACEMENT COST $300. PLASTIC GUIDE IS NOT AVAILABLE SEPARATELY SO YOU MUST BUY THE ENTIRE HYDROLIC TENSIONER. ANOTHER MODEL, PORSCHE 928S AND 928 S4 USE THE SAME TENSIONER SO THEY ARE AFFECTED AS WELL. THE PROBLEM SEEMS TO BE ARISING AT ABOUT 60-100,000 MILES. THIS MAKES MOST OF THE CARS ABOUT 8-11 YRS OLD SO THE PROBLEM IS BASED ON TIME/USE ISSUE. I CANNOT UNDERSTAND WHY PORSCHE WILL NOT ADDRESS THE PROBLEM. I HAVE THE TENSIONER AVAILABLE FOR REVIEW AND CAN PROBABLY GET MORE FROM OTHER OWNERS AS WE ALL COMMUNICATE REGULARLY ON WWW.RENNLIST.COM. *AK