2003 mariner 60hp efi 4 stroke bigfoot warning bleep

"hi ,, took boat out today its

"hi ,, took boat out today its fitted with 2003 mariner 60hp efi 4 stroke bigfoot ,the boat started up and was going as normal but when i opened the throttle within 5 minutes the continuous warning bleep sounded this happened at 4500 rpm and the engine sort of started to jump around a bit like it was misfireing fuel starvation etc,, when i dropped revs down to 1000rpm the bleep stopped ,, water from the tell tell is as normal nice strong flow ,, i opened the throttle again and as it gathered speed it done the same again ,,any ideas or common faults what could be causing this to happen and what steps should i take to try to solve this as would like to know for sure whats up before taking to marine engineer for repair hopefully something simple i can do myself
any help would be great and much appreiciated
many thanks
ady"

"Unfortunetly i think your jus

"Unfortunetly i think your just going to have to take that engine to a mercury dealer, and get it hooked up to the diagnostic software."

"Adrian would have to agree wi

"Adrian would have to agree with the above advice. Your motor has a "guardian" system onboad. If it detects either an overheat, low oil etc (whether actual or just a bad sensor) it will restrict the rpms by cutting the fuel, spark or both to keep the motor at (what it thinks is) a "safe" rpm.

A diagnostic will quickly determine if you have a faulty sensor..."