2003 140 4 stroke

[Billfishon1205]

I have a 2003 140 4 stroke that is firing on only cylinders 2 and 3. Have had it hooked up to check ECM and it checks out good,
I have been told by a Suzuki service person that various safety items- oil pressure, heat and reverse drops out cylinders 1 and 4. Is this in fact true? Where should I go from here?????

[artdf175]

Well that is a new one. I have not run across anything like that
A little more information might help
Under what conditions is this happening?
Any alarms? What rpm ?
Is there no spark to 1 & 4 at all?
There are a couple of good mechanics on the board so maybe with some more info they may be able to help

[Billfishon1205]

There is no spark to cylinder 1 and 4. This limits RPM to 3000 when the boat is in the water. I have been told that when in reverse this should happen or if one of several safe modes- overheat, oil pressure these 2 cylinders drop out????

[artdf175]

I would order the full service manual for your motor
there are step by step instructions on what needs to be checked
with it running in the safe mode there should be some alarms and alarm lights going off..
do you have the engine hooked up through a NMEA wiring to a chart plotter?
how did you determine there was no spark in #1 #4
hard to think both coils, plugs went bad at the same time
it was suggested to get some of the basics checked first.. compression, dirty injectors fuel filters ..
and you could also swap around the coils from one cylinder to another to see if you had a bad coil.. check your plugs by putting them on a coil you know is working to make sure the spark properly..
keep giving feedback

Art

//thanks Grant!!//