At aproximatley 60000 thou miles one of the pistons lost compreshion . we found that it was the rings. my mechanic said that it would be worth rebuilding so I spent apx 3500.00 to repair. Now at eighty thou miles the same thing has happened again. Why? the mechanic said it was just a fluke for it to hapen the first time. He rebuilt the head new rings and pistons . Mic ed everything and said everything was within specks. was there a problem with the 1988 1.5 L mitsubishi enjine