took the boat out the other week after a service with new plugs, fuel water separator, oil, oil filters, cleaned air filter and the port engine wont go past 4000rpm,
no alarms and engine run fine up to there, keep pushing the throttles forward and nothing happens, can trim it out and gain maybe like 100rpm?
i made sure that the throttles were getting full travel on the engine
i have swapped the ait sensor with stbd side but had no change, have fitted a new map sensor but haven't had time to take it for a run
it had half a tank of year old fuel we filled it with fresh fuel
stbd engine is running fine
only done about 15hrs
when i did the service i couldn't undo the fuel filter housing on the back of the engine, was swinging on a spanner with it in a vice and it wouldnt undo, plus i didnt want to distort the housing and put boat out of action, but would it throw up a low fuel pressure alarm if filter was blocked?

wheres the knock sensors?, was thinking of swapping them

there is abit of soot on the transom around the exhaust after the run

ideas on what i could look at?

Get the engine scanned. It's probably in guardian mode for some reason.

I would certainly say that it's in power reduction mode for some reason. Scan the ecm to find out why. My guess would be the cam sensor.
Eddie

^^^^ agree with Eddie 100 % about all of that ^^^^ also look at available power from the scan

Could you guys post where to get a scanner for the 525 again please. Mine's running fine but I'd like to have one.

www.rinda.com
Best ~$500 you will ever spend on your boat.

Iac stuck open.

you need the ECM / PCM 555 adapter with the basic Rinda scan tool. The techmate Pro hand held. Cost for what you need will be about 600 bucks plus shipping unless you add more adapters..

I bought the scanner a month or 2 ago for 499 plus shipping with 555 adapter directly from Rinda. When you call up they will ask you what adapter you want. They were fast to ship, had mine in 2 days.

Exactly my experience a few weeks ago.