HELLO FRIENDS. I HAVE 2000 MODEL 206 XR AUTOMATIC VEHICLE. EXPLOSION SOUND COMES FROM EXHAUST. MORE ACCURATE THE EXPLOSION UNDER MY FOOT. WHEN I REMOVE 60 AND HIGHER SPEED, WHEN I DRAW MY FOOT FROM THE GAS, THERE ARE sometimes bursting with a LOW SOME SOUND SOUND. THE MOTOR IS FREQUENTLY WHEN HOT. THEY SAID THERE ARE NO PROBLEMS ABOUT FUEL. WHEN I RECEIVED THE VEHICLE THE CATALIZER WAS NO THAN THAT THEY MAY HAVE I got the new one changed. SOME TIME IS COMING 2-3 DAYS SOUND DOES NOT COME. Sometimes, 10 KM EXPLOSES 3-4 TIMES. I am waiting for your help and suggestions.