mercruiser engine trouble

[randyaba]

Please help I have a 2007 formula 27 pc with two mercruiser gen 3 5.0 mpi . problem is at mid to top end starboard engine is running 200 rpm lower than port engine have changed cool fuel cartage and disc filter [no paint chips any where] also changed cap and rotor . seems to run fine other wise not sure what to try next or if its the engine giving the trouble

 

[Bt Doctur]

verify the rpm of both engines with a remote tach
verify fuel rail pressures
Remove fuel injectors and send out for cleaning and calibration