Evinrude E-NATION, for those dedicated to water, power, fishing and fun
Posts: 1
Registered: ‎06-18-2018

40hp EFI 4Stroke outboard misses at full throttle. Possibly voltage related?

Hey everyone im hoping you can help me out. I have a 2000 Evinrude 40 horse four stroke efi. At wide-open throttle it intermittently misses. I ran it for three hours yesterday with no problems and then all the sudden it started doing it. I’ve change fuel pump, cleaned injectors replaced all fuel lines. New gas, made sure the tank is clean. I have replaced the spark plugs. I think I’ve pretty much ruled out that it’s fuel related. The bulb is also hard while this is happening. Here is the weird thing that I’ve noticed. At about half throttle my voltage gauge reads about 13 to 13.5 V. At wide open throttle, it climbs up to 14 V and as soon as the voltage reaches 14 the engine starts to act up. If I hold the trim button down to drop the voltage it runs great. If I release the button the voltage jumps back up and again as soon as it hits 14 it starts acting up again. I have also checked the regulator/rectifier with a ohmmeter and it checks out fine. I am completely stumped hear any thoughts?
Posts: 9,459
Registered: ‎07-14-2011

Re: 40hp EFI 4Stroke outboard misses at full throttle. Possibly voltage related?

From your description, it could be a faulty regulator. Make sure there are no wing nuts on the battery and that all grounds are clean, shiny, and secure. 


If the problem continues, you may need a tech to ride along with you while they have the diagnostic software connected to the motor with a laptop and monitoring it before and as the problem develops.




"There is never just one thing wrong with a boat";
                    -- Travis McGee, main character in a book series by John D. McDonald 



The factory recommends that a properly trained technician service your Johnson or Evinrude outboard motor. Should you elect to perform repairs yourself, use caution, common sense, and observe safety procedures in the vicinity of flammable liquids, around moving parts, near high-temperature components, and working with electrical or ignition systems.

The information offered here is only general in nature and should not be construed as complete factory approved procedures, techniques, or specifications. Always use the proper service manual for your motor, up-to-date service literature, the correct tools, and have an understanding of how to proceed with troubleshooting and repair methods. If you are unsure or uncomfortable with a procedure, a situation, or a technique, enlist the services of a factory trained technician.