2015 df15 efi

[Cyrus747]

I have 15 hp 4 stroke. I loved the idea of efi and the light weight. I've had a couple issues but one seems to persist. It seems at times my outboard won't rev up to full rpm at times and almost like it goes into a safe mode. Ive tried re starting to reset it and nothing works...then the next thing you know at full throttle I feel almost like a shift of a gear and the engine goes back up to top speed. My dealer can' figure it out. Anyone have any ideas??

[Solarman]

It could very well be going into safe mode, if trying to "rev up to full rpms". They added that extra protection feature just to prevent people from doing that.

I'm not understanding your other section...

"then the next thing you know at full throttle I feel almost like a shift of a gear and the engine goes back up to top speed. My dealer can' figure it out. Anyone have any ideas??"

this isn't very helpful for a discription?

Good Luck.

[artdf175]

I agree with Solarman. not enough information
On some ways it almost sounds like a fuel tank breather issue
Art

[Cyrus747]

So basically I'm at full throttle and the engine is not revving up to where it should be. There is no bog or anything it just does not seem to power up and can' plane.Than what sometimes happens is I feel a surge or shift in the engine and then suddenly I'm back at full power and speed. Other times it is fine from start and dont have the issue. I use 94 octane chevron since buying new.

[pniksnut]

fuel pump. whats the fuel pressure on the injector rail

[Cyrus747]

Where do I check that??

[artdf175]

what is the fuel bulb doing? it is staying full and hard or collapsing?
I would be more inclined to think you have a fuel delivery problem vs a fuel pump issue
Art

[gordonm1]

You've already heard from the pros above and I can see why the dealer has problems diagnosing an issue that happens at wide open throttle. That's hard to duplicate in a shop. Could be one of the ball valves in your quick connector fuel line is sticking, gummed up, or has debris. This would mean not enough fuel is the problem and I think your fuel bulb would not stay hard when there is a restriction before it. A restriction after it might not present the soft fuel bulb I'm not totally sure on that though.

My 15hp bogs sometimes but it is from too much weight in the boat and I need to try dieting or get a bigger motor.

[Cyrus747]

I'e always thought it was a tad soft as I can squeeze it down when running. My tank doesn' breathe well and I usually keep the cap loose

[artdf175]

ok. what is your fuel tank configuration? external or built in?
some tanks have an anti siphon fitting ball bearing with spring if so it punch out
do you have a water fuel separator filter?
would suggest getting a small portable tank with a new hose and try that as a test
also make sure all the hose fittings are connected properly and tight so no air can get sucked in
art

[Cyrus747]

It' external. The one that came with the outboard.no separator that I know of. Suzuki said the tank was fine but even with the vent fully open I open the cap and a huge gush of air comes out. Hence the reason I leave the cap loose

[artdf175]

I think that would be a good place to start by getting that resolved. If it is one of those caps with a center vent screw, could be gunked up, suggest taking apart and using a pressure hose to clean it out
then check the the tank fitting for that backflow device.
another idea take the fitting off the fuel line that attaches to the engine. First pump fuel back into the tank to be sure it flows correctly then put your fuel cap back on and pump fuel into a container, a good quart to make sure it is venting properly.
another thing to be aware of when everything is hooked back up and that is the position on the fuel bulb , it needs to be mounted vertically and remembering bulb is directional with the fuel flowing the direction of the imprinted arrow-
let me know what you find.. Art

[RagtopRon]

I'm having the same problem. New DF15efi is in break-in period but stutters at WOT ...red caution light comes on simultaneously. When I say it "stutters" I don't mean that it bogs down. I mean, it does but it's more like...it actually intermittently cuts out...and will continue to do so until I roll back the rpms. Manual says that light also indicates "Diagnosis System." Then again, I ran it the other day and didn't have this problem. ANYONE GOT A CLUE? Also, there's something askew with the new portable gas tanks. I have to leave my lid loose, as well...because although the tab says it's open (vented) it obviously ain't because my tank will swell up like a basketball. I need to find an old lid with stainless vent screw and use it on my new tank.

[Captron]

I'm having a problem with my 2017(47hr) DF15A going into power reduction mode(red light comes on and reduced power) took it to a dealer and they said they could not fine anything and no code. It does fine on the stand but under load on my dingy it always does it. Starts and runs great, idles fine and I always flush it and don't use non-ethanol fuel. I put it on stand with a hose and ran great, then on the dinghy and right back. Dealer was useless, I just want it fixed as I'm sailing full time now and got this engine in hopes of trouble free running... Thanks, Capt Ron

[Chillios]

I am having the exact issue. This was my first winter with the motor that is used for a tender. Motor was services in the spring, new plugs, etc. I have a new fuel tank that appears to be venting properly, (no collapse of the ball) I can run at idle for an hour, I can even run full throttle for a moment, but any sustained load and the overheat light comes on. (Head temp is ~163F)

Were you able to find a resolution?