I am working on a 2001 Yamaha F80 that is missing on cyl #4. Spark is present on all 4 cyls. When I take #4 plug wire off, while running, no change in engine sound. Compression on all 4 cyls is 200+ PSI. I have gone thru all 4 carbs and cleaned and reinstalled and still have the same problem. Some questions: Can I use the blinky light tool or PC hook up on this engine? I could not find the plug for either. I don't hear any beep when the key is turned on, I need to check for buzzer operation. Should I hear a beep upon key on? I know that #1 & #4 fire at the same time, but, when I remove spark plug wire while running it will faulter for #1 but not #4. This leads me to believe it to be a carb problem, but, I can spray fuel directly in #4 cyl with no change in engine miss. Also, this miss is occuring at all speeds. I am perplexed, as I am getting the same spark on #1 & #4 but no power on #4. Thanks in advance for any help you can give me.
