Max rpm is only 5000 at wide open. every now and then itll pick up and run about 5800 rpm which the boat speed increases 15mph. some times on the water max rpm is 5000 and itll randomly shoot up for 5800 for 2 mins and sometimes it wont get to 5800 at all... what could be the problem... this is what i have done already..
cleaned vst filter
changed plugs
drained all fuel and replaced
drained all oil and replaces
changed fuel filter
i did a coil/plug test by disconnecting the coil while the motor is running. all cylinders change accept the top 2. i swapped the coils of the top two cylinders and did the test again. same cylinders do no change. that shows me something is apparently wrong with the top 2 cylinders. but what? compression is fine. i ran injector cleaner through the last 4 tanks of fuel. could it be the two injectors? at $220 a injector id rather not try unitl im 100% thats what it is. it doesnt sound like an injector issue if it comes and goes...
any ideas would be helpful before i take it to the boat shop and get ripped off. thanks
cleaned vst filter
changed plugs
drained all fuel and replaced
drained all oil and replaces
changed fuel filter
i did a coil/plug test by disconnecting the coil while the motor is running. all cylinders change accept the top 2. i swapped the coils of the top two cylinders and did the test again. same cylinders do no change. that shows me something is apparently wrong with the top 2 cylinders. but what? compression is fine. i ran injector cleaner through the last 4 tanks of fuel. could it be the two injectors? at $220 a injector id rather not try unitl im 100% thats what it is. it doesnt sound like an injector issue if it comes and goes...
any ideas would be helpful before i take it to the boat shop and get ripped off. thanks