optimax 150hp engine alarm

[bazza]

I took my rib out last weekend for the first time in 4 months. After a slow 5 knts out of the harbour, I opened the throttle halfway but the alarm went off and "reduce throttle" and "guardian" came on. I immediately pulled the throttles back and the alarm silenced. I tried twice more and the same happened. I then revved the engine in neutral and it worked fine, throttled up and away it went. We were out for about an hour with no more problems but on the way back at the same spot(the entrance to the harbour) the alarm went off again with the same warnings.

Can there be something causing interference with the engine system and causing spurious alarms? or does my engine have problem?

Is it just coincidence that it happened at the same spot?

Bit confused over this one. Any help appreciated.

[jambo]

Bazza PM sent
J