MY FRIEND HAS A JOHNSON 115 HP V4 MOTOR THAT SOUNDS LIKE IT IS SKIPPING A LITTLE BIT AT FULL THROTTLE. WIRES AND PLUGS HAVE BEEN REPLACED. SEVERAL TANKS OF GAS HAVE BEEN RUN THROUGH IT.IT ONLY DOES THIS AT HIGH SPEED.PROBLEM STARTED ABOUT 1 YR. AFTER PURCHASE.ANY SUGGESTIONS?
I HAVE A 1988 MERCURY 150 BLACK MAX-V6. RUNNING DOWN THE LAKE RUNNING FINE. BACKED OFF TO SLOW DOWN TO IDLE. AT THIS TIME,STARTED RUNNING ROUGH.TRIED TO TAKE OFF AGAIN BUT ONLY CHOCKED DOWN.I DID A TEST WHILE IDLEING. PULLED THE PLUG WIRES OFF 1 AT A TIME. LOOKING AT THE ENGINE FROM THE REAR...
