Logo

DF20A problem

Rossman

New member
I am scratching my head over an issue that has just cropped on my 2013 DF20A. I have on a 14 ft tin boat that I use on the ocean in Mexico where I live. Two days ago when I launched, the first thing I noticed was that it did not idle down as low as it normally does. Probably between 1000 to 1100 rpm instead of the normal 850. After it warmed up, I got a flashing red light. One flash every 3 seconds but only in neutral. Not to be confused with the change oil warning which flashes every second in every gear until canceled. The engine ran fine most of the morning except for the idle down issue. Late in the morning it started to miss occasionally. It was a funny violent kind of a miss that shook the boat. The first few times it happened I was trolling among dolphin and I actually thought I had hit one of them with my prop. As the morning wore on the frequency of he misses increased until it was happening every second or so. I was even happening at idle in forward but in neutral it seemed to run very smoothly although still a bit higher than usual. I limped in and did some checking and cannot figure out what the problem is. Reseat a bunch of connectors, changed oil again, changed plugs, checked compression, checked the injectors, and some of the sensors and everything looks normal. Any ideas?
 
Did you ever solve this issue with the idle?

Yes, I did. The idle issue turned out to be the ECU. Replaced it and the idle issue and red light went away. The engine missing issue was actually not misfires but worn pinion and forward gear in the lower unit due to water ingress. Fixed everything myself and put 4000 hrs on the motor before replacing it with a 2019 Zuk of the same model.
 
interesting..thus is my issue. I have a 2021 DF9.9B EFI, with 36 hours on it. This isuues has only occured twice, once during break in and again at 35 hrs. The issue is that i can be crusing along at about 3000 rpm say for about 10 minutes or so. Then when I back off the throttle the rpms hang at at about 1200rpms instead of dropping to 850 rpm like it normally does. Its does slowly drop down to 850 rpm over a period of a minute or two but not right away like it normally does. Any idea what might be going on? TPS or ECU maybe? Both time I would shut it down when the idle dropped to 850, then it restarts and runs perfect. I should say i was pushing a pretty heavy load with the family in the boat, and ive never had any warning lights trigger. It always starts 1st pull and runs perfect otherwise. Any input is much appreciated, thanks very much.
 
interesting..thus is my issue. I have a 2021 DF9.9B EFI, with 36 hours on it. This isuues has only occured twice, once during break in and again at 35 hrs. The issue is that i can be crusing along at about 3000 rpm say for about 10 minutes or so. Then when I back off the throttle the rpms hang at at about 1200rpms instead of dropping to 850 rpm like it normally does. Its does slowly drop down to 850 rpm over a period of a minute or two but not right away like it normally does. Any idea what might be going on? TPS or ECU maybe? Both time I would shut it down when the idle dropped to 850, then it restarts and runs perfect. I should say i was pushing a pretty heavy load with the family in the boat, and ive never had any warning lights trigger. It always starts 1st pull and runs perfect otherwise. Any input is much appreciated, thanks very much.

I think the TPS or air flow sensor are a good place to start. Doubt it's an ecu problem. Also you want to make sure there is no binding in the cables under the cowling and to the tiller if it is a tiller model, or to the remote throttle if not. You mentioned pull start so most likely a tiller.
 
Okay thanks. Not too worried about it yet as it's only happened twice and sorted itself out right away. Yours was the only other post I could find mentioning the strange Idle issue. Anyways you seem like you probably know your way around the motor pretty well so I'm wondering if you know what this plugged off nipple on the top of the vapor separator tank would be for? I will try to upload the picture.Screenshot_20220910_042014.jpg
 
Back
Top