2004 Mercury 225hp EFI help!

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Hey guys, I’m a little stumped and hope can get some help

I have a 2004 225hp merc EFI, running rough and no power

from what I can see 2 of 6 cylinders aren’t doing anything

compression is 100-105, not greatest but not terrible

the 2 cylinders that I suspect have super clean plugs, put brand new ones in and they don’t seem wet, no carbon on them like new, the other 4 had normal wear from running 20 minutes

i Checked the spark of course, has spark, I suspected injectors, put a new injector in one, same this plug always looks new

tested pulse at the injector and it has power

what should I test from here ?

has power, has spark, tested injector with a new one but no changes

it’s running very high idle on startup, I have the smart craft hooked up, flashing engine light, showing 2400rpm but don’t think it’s that high

help?? Thanks guys

[Chaz]

I have seen the cylinder head O-ring leak bad enough to "put the spark out" .

Another area to look at is the reed valves. No crankcase compression ,, little to nothing making it's way to the top .

Let us know what you find ..

[rgsauger]

Welcome to scream and fly! Once you get it running, if you have not done so recently, pull all of the injectors and send them to one of the sponsors on here to have them professionally cleaned. They are the lifeblood of your motor.

[OnPad]

How did you test injector pulse?
Which cylinders are getting no fuel?