19th Mar 2014, 10:54
All Mitsubishi Sirius platform performance engines (4G and 6G designators, dual overhead cam) have interference heads. If the timing belt tensioner fails, the belt cannot keep the cams in time. The valves WILL impact the piston face, usually resulting in bent valves, busted valve guides, damaged pistons, and damage to valve seats. Usually it will munch a valve and damage the bowls as well as scoring cylinder walls. In odd cases, it may even bind up on a broken piece of valve and bend a piston rod.
18th Mar 2014, 23:54
Hi, I had the same exact thing happen to my car. The tensioner bolt that holds the tensioner that keeps the tension on the belts. It broke and it killed my engine bad. I ended up destroying 14 of the 24 valves, the front head, and 4 pistons. Grand total of engine work and parts was almost $3,000. Like he said, replace the tensioner bolt too.