F225 May be detonating?

I just replaced a cracked piston on a 2005 F225 with 1400 hrs and over a thousand below 1000 rpm. Actually I ordered them all just incase? Valves were good and I replaced timing belt and it is set properly. Engine starts and runs good but I believe a knock I am hearing at low speed might be detonation? A computer read out is not showing any faults? Is this possible. The motor runs good except the knock? I contacted Yamaha and they were useless?

[boats.net]

Do a compression and leak down test to see it has low compression or a leak past rings. The injector on cylinder with cracked piston should be replaced. Check all injectors.

Compression and leakdown is good. infact new pistons and rings. cylinder walls were good but one of the pistons was cracked through? I tried to enlist yamaha factory to no avail as warrantee was up about a year ago? So I fixed it my self. Are you saying one of the injectors could be the reason for a knocking sound?

[boats.net]

Injectors can cause a lean running condition which can cause detonation. Usually if you hear a knock that was due to detonation it's already too late, piston damage has already occured. Need to check sync and TPS settings, check timing is within specs, condition of fuel and make sure engine is not running too hot.

Thanks , what is sync and TPS setting exactly?

If you could help what is sync and tps ? is that concerning the injectors?

[boats.net]

Throttle linkage synchronization, check service manuals for steps. TPS is throttle position sensor.