Hey all i have a 97 shark 770 montecarlo im having an issue with it and its driving me crazy. One day the machine runs awesome 50mph and it dont miss a beat. the next day it runs the same but then out of nowhere it bogs down and wont do over 15mph. then after an hr of trying to get back to boat launch it fixes itself and runs good again. sometimes the rest of the day sometimes for twenty min. here is what i have done. new plugs battery and new throttle cable. new fuel filter and new tank of fresh fuel. compression on the motor is 120 in one cyl and 130 in second cyl. alot of people say its the coil cause sleds do the same thing